Update README

README.md

@@ -1,3 +1,38 @@
 # ghup
 
 Simple Github helper for myself.
+
+## Installation
+
+If you don't have haskell GHC and cabal installed,
+follow [ghcup](https://www.haskell.org/ghcup/) first.
+
+Then issue:
+
+```sh
+$ cabal v2-install ghup
+```
+
+## Usage
+
+First you need to set the github OAuth (no other method currently supported)
+for API access:
+
+```
+ghup config --oauth "<your-github-token>"
+```
+
+Then follow the help page:
+
+```
+Usage: ghup COMMAND
+
+Available options:
+  -h,--help                Show this help text
+
+Available commands:
+  fork                     Fork a repository
+  config                   Set ghup config (such as OAuth)
+  delete                   Delete a forked repository
+  list-forks               List my forks
+```