📝 Add initial documentation on how to use (#3)

README.md

@@ -1,2 +1,29 @@
 # gitmoji-enforcer
-
+
+A simple action to enforce the use of gitmoji in PR titles.
+
+It will leave a comment on the PR like so:
+https://github.com/georgepstaylor/gitmoji-pr-title-enforcer/pull/2#issuecomment-2094373552
+or 
+https://github.com/georgepstaylor/gitmoji-pr-title-enforcer/pull/2#issuecomment-2094373635
+Depending on whether the PR title is valid or not.
+
+## Usage
+```yaml
+name: Enforce gitmoji PR
+on:
+  pull_request:
+    types: [opened, edited, reopened, synchronize]
+permissions:
+  pull-requests: write
+jobs:
+  gitmoji-pr-title:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Enforce gitmoji PR title
+        uses: georgepstaylor/[email protected]
+        with:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+```
+
+Using the above example verbatim, you can use the job title `gitmoji-pr-title` as a required check.