As with the bar end shifters below, I found this a little fiddly and would have loved some photos before doing it! If you are going to do this, I recommend having an array of Allen keys (long and short) as the space in which you have to turn the bolt is small, and the bolt can be quite tight!
Step 1: Un-clip the Brakes
Step 2: Pull down Brake Lever, Insert Allen Key, Turn anti-clockwise to loosen
Step 3: Once loose enough, move brake levers around and off the end of the bar.
This was also quite easy, but a little fiddly loosening the Allen key bolt inside the brake lever. You can actually remove the whole lever from the bracket if you unscrew totally, but it is probably just as easy to loosen it enough, and it should slide around the bar (I had to loosen it a lot more than I anticipated as the bar is a bit thicker at the ends and round the bends).
Hope this helps!