Add Usage section to README

Author: shyiko

README.md

@@ -6,4 +6,26 @@ It enables management of ClickHouse clusters (running inside your Kubernetes clu
 wherever they may be) through Altinity.Cloud. 
 
 At present, this repository is used only to distribute pre-built `altinitycloud-connect` binaries.  
-The source code is scheduled to be released once we're out of Beta. 
+The source code is planned to be released once we're out of Beta. 
+
+## Usage
+
+### CLI
+
+Download pre-built binary from [GitHub Releases](https://github.com/altinity/altinitycloud-connect/releases) page.  
+Sign in to the [Altinity.Cloud Management Console](https://acm.altinity.cloud/), grab environment connect token & then 
+exchange it for a certificate:
+
+```shell script
+altinitycloud-connect login --token=REPLACE_WITH_ALTINITY_CLOUD_CONNECT_TOKEN
+```
+
+Kubernetes cluster can now be connected with
+
+```shell script
+altinitycloud-connect kubernetes | kubectl apply -f -
+```
+
+### Terraform
+
+See [altinity/terraform-altinitycloud-connect](https://github.com/altinity/terraform-altinitycloud-connect).