You want to swap BfB and Litany with DS. This allows Blood to catch your buffed Wheeling Thrust. You may need to delay BfB slightly into your next GCD, depending your skill speed. Basically, pop Litany then watch your GCD and press Blood right before Disembowel can be used. The goal is always try and squeeze nine GCDs in a Blood window. You also want to swap Spineshatter and Dragon Fire. This is what it should look like...

http://ffxivrotations.com/1boi

You can use Diversion pre-pull as it doesn't really matter. In most fights, you want to Elusive right as the tank's about to pull. That way you start, you get in an extra auto plus can hit Heavy Thrust slightly faster without pulling yourself since Elusive doesn't trigger aggro until you actually land. Another tip for maximizing is to delay your Life of the Dragon phase. When your extra Jump comes off CD, hold the Mirage Dive and use Geirskogul first. Sit on your three Eye stacks until Geirskogul's off CD then set up LotD. This allows you to line up your last Nastrond cast with your next BfB.

https://youtu.be/oyJcOUw8mmM

This video guide covers pretty much everything on how to optimize DRG.