I was bored one day and saw the Glyph of Preparation, and thought it'd be fun to make a combat/sub spec. Well i started looking at it. I know it won't be top dps, but i do want it to be able to do something. So i was hoping that we could get some advice on maybe how to improve the spec, or maybe help on a rotation

Spec: http://www.wowhead.com/?talent#fZ0gV0xsxoru0xZxbcdhGzdq 0/40/31

Glyphs: Adreneline rush, Hemorrage, Backstab