I leveled 85-90 with my rogue and mobs died before I could get 5 points spamming sinister strike & slice & dice.
Hardly take any damage with their defensive cooldowns, and If you do then just keep your heal up.
Open fight with:
1 point sinister strike
Slice & Dice
Revealing Strike for sinister strike debuff
Sinister strike till 4-5 points and use Eviscerate or Recuperate (heal) If you need it.
When pulling more than 1 mob then use Blade Flurry coupled with Killing Spree or with 1 mob with alot of health just use Killing Spree when you're low on energy and Slice & Dice is up.
Also learn to use your defensive cooldowns.
Kick to cancel spells.
Cloak Of Shadows If you have alot of spell damage incoming.
Evasion & Combat Readiness If you pulled too many mobs.
Dismantle to remove weapons on melee mobs.