It's hard to cover everything involved in 255 characters; with that in mind there is a mod call the Macro Toolkit which extends the macro box. Once loaded type /mac to open the dialog, create a new macro, click the extend macro button and paste the full version in the macro dialog, save and your done.
http://www.curse.com/addons/wow/macro-toolkitNow as to the macro itself; if you want to run the full thing you will need to install the above mod; unless your happy with the shortened version which has the basics and requires no additional tinkering.
You can hit one button which will- Cast Adrenalin Rush (while in combat spec)
- Start attacking
- Go through your rotation including...
Sinister Strike, Slice n Dice, Eviscerate, Revealing Strike, & Crimson Tempest
The full version will also- Ambush from stealth
- Cast Marked for Death (as well as Adrenaline Rush)
- Use a Trinket (the /use 13 can also be /use 14 depending on slot)
- Stealth you if there are no enemies near
- Target the next enemy
Things not covered in this macro- Killing Spree - you have a buff which rotates over time called Shallow Insight -> Deep Insight (when it's red) you should save your KS for when you have Deep Insight and when your energy bar is low since you won't be able to use abilities when KS is active
- Blade Flurry - Use when fighting multiple mobs; pairs well with Adrenaline Rush.
Shortened Version/startattack
/castsequence reset=target Sinister Strike,Slice and Dice,Sinister Strike,Sinister Strike,Sinister Strike,Eviscerate,Revealing Strike,Sinister Strike,Sinister Strike,Crimson Tempest,Sinister Strike
/cast [combat]adrenaline rush
Full Macro/startattack
/castsequence [stealth]reset=target ambush,!revealing strike
/castsequence reset=target Sinister Strike,Slice and Dice,Sinister Strike,Sinister Strike,Sinister Strike,Eviscerate,Revealing Strike,Sinister Strike,Sinister Strike,Crimson Tempest,Sinister Strike
/cast [combat]adrenaline rush
/cast [combat]!Marked for Death
/use 13
/cast [mod] Killing Spree
/cast [nostealth,nocombat] Stealth
/targetenemy [noharm][dead]