docs: remove a preference for the chat.postMessage method

README.md

@@ -138,15 +138,16 @@ messages or [uploading a file][files.upload] with the convenience of the
 The exact Slack API [method][methods] used will require setting various sets of
 [scopes][scopes], but setup should be similar for all methods:
 
-- [Create a Slack App][apps] for your workspace or use an existing one.
-- Add the [`chat:write`][chat:write] bot scope under the **OAuth & Permissions**
-  page.
+- [Create a Slack app][apps] for your workspace or use an existing app.
+- Select a [method][methods] to call and add the required **scopes** to your app
+  under the **OAuth & Permissions** page on app settings.
 - Install the app to your workspace using the **Install App** page.
-- Copy the app's Bot Token from the **OAuth & Permissions** page and
-  [add it as a secret in your repo settings][repo-secret] named
-  `SLACK_BOT_TOKEN`.
-- Invite the bot user into the channel you wish to post messages to
-  (`/invite @bot_user_name`).
+- Find the [token][tokens] minted for the Slack API method being called from the
+  **OAuth & Permissions** page.
+- Add the token as [a repository secret][repo-secret] called `SLACK_BOT_TOKEN`
+  or something similar and memorable.
+- [Add this Action as a step][job-step] to your GitHub workflow and set the
+  input payload to send.
 
 #### Usage