docs(contribute): improve git instructions

Author: rctay

docs/content/misc/contribute.ngdoc

@@ -256,31 +256,27 @@ To create and submit a change:
    [print, sign and one of scan+email, fax or mail the form](http://code.google.com/legal/corporate-cla-v1.0.html).
 
 
-2. Create a new branch off the master for your changes:
+2. Create and checkout a new branch off the master branch for your changes:
 
-        git branch my-fix-branch
+        git checkout -b my-fix-branch master
 
-3. Check out the branch:
+3. Create your patch, make sure to have plenty of tests (that pass).
 
-        git checkout my-fix-branch
-
-4. Create your patch, make sure to have plenty of tests (that pass).
-
-5. Commit your changes and create a descriptive commit message (the commit message is used to generate release notes,
+4. Commit your changes and create a descriptive commit message (the commit message is used to generate release notes,
    please check out our
    [commit message conventions](https://docs.google.com/document/d/1QrDFcIiPjSLDn3EL15IJygNPiHORgU1_OOAqWjiDU5Y/edit#)
    and our commit message presubmit hook `validate-commit-msg.js`):
 
         git commit -a
 
-6. Push your branch to Github:
+5. Push your branch to Github:
 
         git push origin my-fix-branch
 
-7. In Github, send a pull request to `angular:master`.
+6. In Github, send a pull request to `angular:master`.
 
 
-8. When the patch is reviewed and merged, delete your branch and pull yours — and other — changes
+7. When the patch is reviewed and merged, delete your branch and pull yours — and other — changes
 from the main (upstream) repository:
 
   1. To delete the branch in Github, run: