[readme]: add usage docs

legomushroom · web-flow · commit 02602eb6a0d3 · 2022-03-17T19:56:49.000Z
diff --git a/README.md b/README.md
@@ -6,4 +6,10 @@
 gh extension install legomushroom/gh-net
 ```
 
+### Usage
+
+```shell
+gh net start
+```
+
 [About GitHub CLI](https://cli.github.com/)
