I do it manually through moving my S/L to lock in profits using either the 15 min or the 1hr charts. If the market is ranging, I act on the 15 min chart in order to be more conservative with my profit taking, but if the market is trending like it was doing two weeks ago, I am much more liberal and use the 1hr chart. This means you have to be able to constantly monitor your position and therefore won't work for everybody, but it's a very basic strategy and works better in my opinion than a static T/P.