Update README.md with Development guidance (#852)

- Add a new Development section to integrate tools
- Expand Pull Requests guidance
- Add a cool WebNN logo!

Author: anssiko

README.md

@@ -1,29 +1,59 @@
 [![build](https://github.com/webmachinelearning/webnn/actions/workflows/auto-publish.yml/badge.svg)](https://github.com/webmachinelearning/webnn/actions)
 
+![](https://webmachinelearning.github.io/logos/webnn/logo-webnn-white.png)
+
 # Web Neural Network API
 
 This repository hosts the [Web Neural Network API](https://www.w3.org/TR/webnn/)
 being worked on in the
 [Web Machine Learning Working Group](https://www.w3.org/groups/wg/webmachinelearning).
 
-## Pull requests
+To join this Working Group, please see these [instructions](https://webmachinelearning.github.io/community/#join).
 
-To propose a change, update `index.bs` and submit your PR. The `index.html` file is automatically built and deployed upon merge.
+## Development
 
-The spec is written using [Bikeshed](https://tabatkins.github.io/bikeshed). Please refer to the [Bikeshed Documentation](https://tabatkins.github.io/bikeshed/) for the Bikeshed syntax.
+This section describes the process for building this specification on your local computer for development and testing purposes. You may want to do this before you submit a [Pull Request](#pull-requests) to catch possible build issues early.
 
-For testing purposes, you can generate the spec locally:
+The first step is to clone the repo:
 
-If you have bikeshed [installed locally](https://tabatkins.github.io/bikeshed/#installing), you can generate the specification locally with:
+```
+prompt> git clone https://github.com/webmachinelearning/webnn
+```
+
+Next, install the makefile dependencies:
 
 ```
-prompt> make
+prompt> cd tools
+prompt> npm install
+prompt> cd ..
 ```
 
-This simply runs bikeshed on the `index.bs` file.
+Now you can choose between the two options:
+
+- [Install Bikeshed locally](https://speced.github.io/bikeshed/#install-final) (works offline, faster build) and run:
+
+```
+prompt> make
+```
 
-Otherwise, you can use the [bikeshed Web API](https://tabatkins.github.io/bikeshed/#remote):
+- Or use the [Bikeshed HTTP API](https://speced.github.io/bikeshed/#remote) (requires internet, slower build):
 
 ```
 prompt> make online=1
 ```
+
+In both the cases, the makefile runs [tools](tools) to check the source formatting and catch common errors, and then uses Bikeshed to convert the `index.bs` source file to an `index.html` output file.
+
+If the build is clean you can open the `index.html` file in your browser to view it in all its glory! If you're happy with what you see, congratulations! You can proceed to submit a [Pull Request](#pull-requests).
+
+## Pull Requests
+
+First, please read the [contributing guidelines](CONTRIBUTING.md).
+
+The spec is written using [Bikeshed](https://speced.github.io/bikeshed/) spec-generating tool. Please refer to the [Bikeshed Documentation](https://speced.github.io/bikeshed/) for the Bikeshed syntax and [coding conventions](docs/SpecCodingConventions.md) specific to this specification.
+
+To propose a change to the specification, you are only required to update the `index.bs` source file authored in Bikeshed syntax.
+
+Before you submit a PR, it is recommended to test your changes locally (see [Development](#development)). If your local build is clean, you can proceed to submit the PR. If you want to submit a WIP PR that still contains errors or is incomplete, please [convert the PR to a draft](https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/proposing-changes-to-your-work-with-pull-requests/changing-the-stage-of-a-pull-request#converting-a-pull-request-to-a-draft). As a convention, please [link the PR to an existing issue](https://graphite.dev/guides/how-to-link-pull-requests-to-github-issues) for [non-editorial changes](CONTRIBUTING.md#type-of-change).
+
+After you submit the PR, it is first automatically checked with [GitHub Actions CI/CD](.github/workflows/auto-publish.yml) for common issues and then reviewed by group participants. After adequate review and approvals, the PR is merged and a new version of the specification is deployed at https://www.w3.org/TR/webnn/ ([history](https://www.w3.org/standards/history/webnn/)).