Update README.md

Author: benfeely

README.md

@@ -30,3 +30,41 @@ You can look through the issues (which should be up-to-date on who is working on
 [ard-demo]: https://benfeely.github.io/angular-react/demo
 [getting-started]: https://benfeely.github.io/angular-react/docs/getting-started
 [fab]: https://developer.microsoft.com/en-us/fabric
+
+### Pull Requests
+Locate the section for your github remote in the `.git/config` file. It looks like this:
+
+```
+[remote "origin"]
+	fetch = +refs/heads/*:refs/remotes/origin/*
+	url = git@github.com:joyent/node.git
+```
+
+Now add the line `fetch = +refs/pull/*/head:refs/remotes/origin/pr/*` to this section. Obviously, change the github url to match your project's URL. It ends up looking like this:
+
+```
+[remote "origin"]
+	fetch = +refs/heads/*:refs/remotes/origin/*
+	url = git@github.com:joyent/node.git
+	fetch = +refs/pull/*/head:refs/remotes/origin/pr/*
+```
+
+Now fetch all the pull requests:
+
+```
+$ git fetch origin
+From github.com:joyent/node
+ * [new ref]         refs/pull/1000/head -> origin/pr/1000
+ * [new ref]         refs/pull/1002/head -> origin/pr/1002
+ * [new ref]         refs/pull/1004/head -> origin/pr/1004
+ * [new ref]         refs/pull/1009/head -> origin/pr/1009
+...
+```
+
+To check out a particular pull request:
+
+```
+$ git checkout pr/999
+Branch pr/999 set up to track remote branch pr/999 from origin.
+Switched to a new branch 'pr/999'
+```