title: How to do a pull request in GitHub with only the latest commit in the master branch of my forked repository
body: <p>I forked a repository on github. I made some changes and did a pull request.</p>
  
  <p>Now I made some other changes and want to do a new pull request, but on the preview screen before doing the pull request it shows the old commits too (the ones that were already accepted).</p>
  
  <p>How do I select only the latest commit in the master branch of my forked repository so that I can do a pull request with only that commit?</p>