diff --git a/00-instructors.md b/00-instructors.md
index cb1a33a..9ce6ac9 100644
--- a/00-instructors.md
+++ b/00-instructors.md
@@ -34,3 +34,11 @@ Dr. Wu’s research focuses on geospatial data science and open-source software
 **Founder @ [VorGeo](https://www.vorgeo.com/)**
 
 Dr. Tyler Erickson is the founder of the geospatial consultancy VorGeo, a Technical Fellow at non-profit [Radiant Earth](https://radiant.earth/), and a founding editorial board member of the [Cloud-Native Geospatial Forum](https://cloudnativegeo.org/). Previously he led the developer relations team for [Google Earth Engine](https://earthengine.google.com/). Dr. Erickson's work focuses on building communities & ecosystems around emerging technologies, with an emphasis on technologies that can be leveraged by environmental sustainability projects.
+
+## [Tasha Snow](https://tsnow03.github.io)
+
+**Research Scientist @ [NASA Goddard Space Flight Center (GSFC) / Earth System Science Interdisciplinary Center (ESSIC), University of Maryland](https://essic.umd.edu/)** \
+**Co-Founder @ [CryoCloud](https://cryointhecloud.com)**
+
+I am one of the leads of the CryoCloud community meant to help geoscientist transition to cloud computing, which revolves around a JupyterHub cloud computing platform. I provide training, maintain our environments, and develop data workflows that are idealized for geoscience work in the cloud.
+I'm also a research scientist in the Cryospheric Sciences Lab at NASA GSFC and ESSIC. My research foci are glaciology, oceanography, cloud computing, and open science.
diff --git a/01-prerequisites.md b/01-prerequisites.md
index b2cca4d..8bbcd12 100644
--- a/01-prerequisites.md
+++ b/01-prerequisites.md
@@ -19,9 +19,15 @@ Please [sign up for a GitHub account](https://github.com/signup) if you haven't
 
 ## Complete the CryoCloud onboarding process
 
-Follow the
-[CryoCloud "getting started" documentation](https://book.cryointhecloud.com/getting-started)
-to gain access to CryoCloud.
+1. Fill out this short [Getting Started Survey](https://forms.gle/d8oP1gp9YikS2ixM8) to give us the 
+required credentials and information to get you on the hub.
+
+
+2. Once we have your survey, within the next day or two we will invite you to the CryoCloud GitHub organization and CryoCloudUsers team (you will receive an email when we do this from GitHub **at the email you have linked to your GitHub profile**). Please accept this invitation within 7 days or it will disappear and we will need to resend it. Your membership on that GitHub team provides you with access to the CryoCloud hub.
+
+
+3. Open up the [CryoCloud JupyterHub](https://hub.cryointhecloud.com) to make sure it works for you. 
+You will need your Github username and password to sign on. A 404 error message means you are not yet part of the GitHub org and need to accept the invitation from GitHub first.
 
 
 ### ⚠️ Critical: Accept the invitation to join the CryoCloud team
diff --git a/materials/01-working-in-jupyterhub/bring_own.png b/materials/01-working-in-jupyterhub/bring_own.png
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diff --git a/materials/01-working-in-jupyterhub/index.md b/materials/01-working-in-jupyterhub/index.md
index 3bd3ad8..cf40c42 100644
--- a/materials/01-working-in-jupyterhub/index.md
+++ b/materials/01-working-in-jupyterhub/index.md
@@ -17,7 +17,7 @@ authors:
 :class: dropdown
 
 <iframe
-    src="https://docs.google.com/presentation/d/e/2PACX-1vRe2ACdsZHjAfG_dpS_ZkDjLLG3qizsQCgWBgAXzetJlPz7DKVXWx3nrSfEK-LGEs_H8myf21tQzR9o/pubembed?start=false&loop=false&delayms=60000"
+    src="https://docs.google.com/presentation/d/1BRWaZUEfBJlKA9WL7jIdL_4jlQ24wohS_GNjYJCFliw/edit?usp=sharing/pubembed?start=false&loop=false&delayms=60000"
     frameborder="0"
     width="960"
     height="569"
@@ -34,18 +34,13 @@ authors:
 :::
 
 
-## Access the [CryoCloud powerpoint](https://docs.google.com/presentation/d/1sj5oSAnHQ5Le0zMNqy55T-esZqro-WjVOPJdv_BR08M/edit?usp=sharing) whenever you need to reference it
+## Access the [CryoCloud powerpoint](https://docs.google.com/presentation/d/1BRWaZUEfBJlKA9WL7jIdL_4jlQ24wohS_GNjYJCFliw/edit?usp=sharing) whenever you need to reference it
 
-Open the powerpoint by directly clicking on the hyperlink above or to open it in the CryoCloud Linux Desktop web browser as follows:
-
-- Copy this hyperlink: `https://docs.google.com/presentation/d/1sj5oSAnHQ5Le0zMNqy55T-esZqro-WjVOPJdv_BR08M/edit?usp=sharing`
-- Click on the plus (`+`) sign in the `File Browser` to the left to open a `Launcher` window
-- Under Notebooks, click on `Desktop` to access the Linux Desktop. This will open a new tab.
-- Click on the `Web Browser` tool (globe) at the bottom of the screen
-- Paste the url into the search bar
+Open the powerpoint by directly clicking on the hyperlink above.
 
 ![](./slides.png)
 
+---
 
 ## Open CryoCloud
 
@@ -63,18 +58,157 @@ server and having to rerun your analysis.**
 :::
 
 3) Sit back and learn about each of the tools!
+    - How to bring your own environment
     - JupyterHub options and viewing setup
     - Github
     - Virtual Linux desktop
     - SyncThing
     - Viewing and editing of different files
 
-Now after the demo...
+---
+
+## Bring Your Own environment (custom Docker image)
+
+CryoCloud allows you to launch your server using different software environments. Each environment corresponds to a Docker image, which defines the libraries, tools, and versions available to you. Switching Docker images is similar to switching between computers that have different applications installed.
+
+Using a custom Docker image is useful when you want:
+- A different software stack than the defaults
+- An older or reproducible version of CryoCloud’s environment  
+- A specialized environment from an external registry (e.g., Pangeo, Rocker)
+
+This feature is called **Bring Your Own Image (BYOI)**.
+
+
+### 1. Selecting an environment when launching CryoCloud
+
+When you open CryoCloud, the **Environment** dropdown provides:
+
+- Python  
+- R  
+- Matlab  
+- Other  
+- Build Your Own  
+
+To use a custom Docker image, select **Other**.  
+A field labeled **Custom image** will appear. This is where you will paste the Docker tag for the environment you want.
+
+![](./bring_own.png)
+
+
+### 2. Finding a Docker tag
+
+A Docker tag tells CryoCloud which exact environment to use. You can choose tags from CryoCloud’s maintained images or from Docker Hub.
+
+
+### Option A: Use an older or alternate CryoCloud environment
+
+CryoCloud publishes its Python environment image to Quay.io.
+
+1. Visit the repository tags page:  
+   https://quay.io/repository/cryointhecloud/cryo-hub-image?tab=tags
+
+2. Browse the available tags. Each tag corresponds to a specific version.
+
+3. Copy the full tag in the following form: `quay.io/cryointhecloud/cryo-hub-image:<tag>`
+
+Example:
+
+```
+quay.io/cryointhecloud/cryo-hub-image:e457bd429a1e
+```
+
+Paste the tag into the **Custom image** field on CryoCloud. For reference, this image is built from the code in: https://github.com/CryoInTheCloud/hub-image.
+
+```{image} ./image_tags.png
+:width: 60%
+:align: center
+```
+
+### Option B: Use an image from Docker Hub
+
+You may also use any public Docker image from Docker Hub.
+
+1. Search for images at:  
+   https://hub.docker.com/
+
+2. Tags typically follow this format: `account/image:tag`
+
+Example:
+```
+pangeo/ml-notebook:latest
+rocker/geospatial:4.4
+```
+
+Paste any valid tag into the **Custom image** field.
+
 
+### Example: Using a machine learning environment
+
+If you want a Pangeo machine learning environment, enter:
+```
+pangeo/ml-notebook:latest
+```
+
+CryoCloud will launch your session using that environment.
+
+
+### Tips
+
+- If an image does not launch, ensure it includes a Jupyter-compatible single-user interface.
+- Private images requiring authentication are not currently supported through the UI.
+- Images must be Linux-based and appropriate for JupyterHub.
+- Use explicit tags (not `latest`) when reproducibility is important.
+
+---
+
+## Build Your Own image
+
+CryoCloud also supports creating a fully customized environment using your own `environment.yml` file. This option is useful when you want complete control over the software stack and only want the packages you specify.
+
+When launching CryoCloud, select **Build Your Own** from the **Environment** dropdown.  
+A field labeled **Repository** will appear. This is where you will paste the URL of a GitHub repository that contains an `environment.yml` file.
+
+![](./build_your_own.png)
+
+
+### Example: Using a minimal template repository
+
+You can start with a simple example environment from the following template repository:
+
+```
+https://github.com/tsnow03/BuildOwnImage_template_env.git
+```
+
+To copy the correct link from your own repository:
+
+1. Open your GitHub repository.  
+2. Click the blue **Code** button.  
+3. Copy the HTTPS URL (it should end in `.git`).  
+
+CryoCloud will use the `environment.yml` found in that repository to build your image.
+
+
+### Building the Image
+
+1. Paste the repository URL into the **Repository** field.  
+2. Click **Build image**.
+
+CryoCloud will begin building a Docker image based on your `environment.yml`. Build times vary depending on the number of packages:
+
+- Simple environments: ~30 seconds  
+- Large or complex environments: up to ~1 hour  
+
+If the build process encounters an issue, an error message will appear in the log so you can revise your `environment.yml`.
+
+After the image is built once, you can easily select it again in future sessions.
+
+**Tip:** Test your `environment.yml` locally using Mamba before using Build Your Own to speed up the build process and avoid waiting through repeated failures.
+
+---
 
 ## Task: Clone the CryoCloud jupyterbook
 
-We will import the [CryoCloud Website Github repository](https://github.com/CryoInTheCloud/CryoCloudWebsite.git).
+We will import the [workshop repository](https://github.com/geojupyter/workshop-open-source-geospatial.git).
 
 To do this:
 1. Select the plus (`+`) sign above the `File Browser` to the left, which will bring up a `Launcher` window.
@@ -94,17 +228,22 @@ To do this:
 3. Now clone the hackweek code into your current directory:
 
    ```
-   https://github.com/CryoInTheCloud/CryoCloudWebsite.git
+   https://github.com/geojupyter/workshop-open-source-geospatial.git
    ```
 
 4. You will see the folder pop into your `File Browser` on the left if you have the current directory open.
    Click on the folder to navigate through the files.
 
-5. To open this tutorial, click on the `book` subdirectory > `tutorials` and double
-   click on `CryoCloud`.
+5. To open this tutorial, click on the `materials` subdirectory > `01-working-in-jupyterhub` and double
+   click on `index.md`.
    This should open up this tutorial in case you want to review it in the future.
 
 
+Now after the demo...
+
+
+---
+
 ## Shutting down your JupyterHub
 
 ```{tip}
@@ -121,12 +260,16 @@ We prefer you shut down the server when so we save that 90 minutes of computing
 To do so:
 
 - In upper left, click on `File` > `Hub Control Panel`, which will open another tab
-- Click the `Stop Server` button. Once this button disappears after you clicked it, your server is off.
+- Click the red `Stop Server` button. Once this button disappears after you clicked it, your server is off.
 - Click `Log Out` in the top right of your screen and you will be logged out, or you can start a new server
 - You can now close this tab and the other tab where you were just working
 
-![](./stop_server.png)
+```{image} ./stop_server.png
+:width: 70%
+:align: center
+```
 
+---
 
 ## Summary
 
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