update docs

Author: Gustavo Marin

README.md

@@ -2,30 +2,37 @@
 
 This action can publish an AUR package.
 
+
+## Requirements
+
+It depends on an environment variable called `GITHUB_REF` to be present and it should also contain a semantic version
+in the format `v0.0.0` to work properly.
+
+This tag should also comply with rules established to publish versions on AUR repository.
+
+You should add to your secrets an SSH private key that match your key uploaded to your AUR account,
+so this action can commit and push to it.
+
+
 ## Inputs
 
 ### `package_name`
-
 **Required** The AUR package name you want to update.
 
 ### `commit_username`
-
 **Required** The username to use when creating the new commit.
 
 ### `commit_email`
-
 **Required** The email to use when creating the new commit.
 
 ### `ssh_private_key`
-
 **Required** Your private key with access to AUR package.
 
 
-
 ## Example usage
-
 ```
 name: aur-publish
+
 on:
   push:
     tags: