/run if GetUnitName("target")==nil then TargetNearestEnemy() end 
	/run if not IsCurrentAction(8) then UseAction(8) end 
	/Cast Sinister Strike 
	/run UIErrorsFrame:Clear()   
	Place auto-attack on bar-spot 8 (or change the macro to whatever fits your purpose) 
	This targets nearest enemy, starts attacking and casts SS. Swap for backstab if daggerspecced