Update docs for merging master into feature branch

x-pack/legacy/plugins/integrations_manager/README.md

@@ -6,21 +6,25 @@ We're using a long-running feature branch [`feature-integrations-manager`](https
 
 <details>
   <summary>Keeping up to date with upstream kibana</summary>
-
-[jfsiii](http://github.com/jfsiii) will keep the branch up-to-date with `master` by periodically running `git merge master` locally and pushing. [This PR](https://github.com/elastic/kibana/pull/38255#issuecomment-499839073) has more information.
 
 ```bash
-# checkout the elastic/kibana feature branch locally; overwriting any existing feature-integrations-manager
-git checkout -B feature-integrations-manager upstream/feature-integrations-manager
+## checkout feature branch to your fork
+git checkout -B feature-integrations-manager origin/feature-integrations-manager
+
+## make sure your feature branch is current with upstream feature branch
+git pull upstream feature-integrations-manager
 
-# fetch & merge latest
+## pull in changes from upstream master
 git pull upstream master
 
-# push back to elastic/kibana
-git push upstream
+## push changes to your remote
+git push origin
 
-# switch back to feature-integrations-manager on your fork
-git checkout -B feature-integrations-manager origin/feature-integrations-manager
+# Open a **DRAFT PR**. Normal PRs will re-notify authors of commits already merged
+# Draft PR will trigger CI run. Once CI is green ...
+
+## push your changes to upstream feature branch
+git push upstream
 ```
 </details>