Quoted from http://hubpages.com/hub/How_to_do_a_perfect_Rogue_Stunlock_in_World_of_Warcraft:
How to do a perfect Rogue Stunlock in World of Warcraft
The key is patience
A perfect stunlock requires a lot of practice and more importantly requires a lot of patience on the part of the rogue. Stunlocks are not the function of a rogue by any means. They are, however, an important tool especially in group vs. group combat.
Here is the sequence for a perfect rogue stunlock in World of Warcraft. It should be noted that deadly poison will make a stunlock impossible, since the dot ticks will break saps, blinds and gouges.
1. Open with a cheap shot. If this misses, the rogue should vanish and try again later. Pushing a bad opener usually results in a loss for the rogue.
2. A cheap shot will give the rogue time for one combo point, so a sinister strike should be used before the cheap shot wears off.
3. The next attack will be a three or four-point kidney shot, which will give the rogue time for one more sinister strike before changing sides.
4. Before the kidney shot wears off, the rogue should move in front of their opponent and gouge. Combat rogues will find this gouge will give them a choice of how to continue. Non-combat rogues have only one choice.
5. From the gouge, the combat rogue will have time to drop combat and restealth. Non-combat rogues have to burn their blind here so they can restealth.
6. Both rogue builds, once re-stealthed, should sap their opponent in order to reset their attack cooldowns.
7. From here, the rogue can cheap shot and start building combo points again, going from steps one through four.
8. Once their opponent has been re-gouged, non-combat rogues will have to vanish in order to start the sequence again. Combat rogues should use their blind here, wait for combat to drop, then restealth.
9. The rogue should continue from steps one and two this time, but replace the kidney shot in step three with eviscerate.
10. If 15 combo points isn't enough to defeat your opponent, form a raid party and come back when the instance timer resets, or just wait until you're at least half your opponent's level.