When I play a rogue, i generally press the buttons until the mans die.
But in all seriousness, I think you use backstab whenever you can and hemo when backstab isn't an option or you need combo points or whatever. Ambush is pretty hard hitting, use it while shadowdancing, ie. cheap > ambush > ambush > ambush.
If the opponent outpositions you in shadowdance, you can shadowstep or gouge to build time.
I have never played a rogue but this is what I'm assuming. Take it with a grain of salt.
Just make sure you pool a full energy bar before shadow dancing, while doing the shadowdance your either going for the kill, or applying mass pressure thus forcing all their main defensive cds in which you would be ready to take the kill soon, or the next shadow dance.
You can also make an attempt to force trinkets without blinding, then once the trinket has been used, get a situation where you can vanish garrote > kidney after siilence, blind, sap, sap , sap garrote > kidney and they SHOULD DEFFINATELY be dead.
About hemmo, personally I find the damage awful, I mainly use backstab, if for any circumstance you absolotly CANNOT backstab, then you can hemmo. Same with Rupture, I never rupture, its a waste, the damage is poor like really poor.
There is 2 ways you can reforge, either mastery or haste, personally I prefer haste and overall it is better due to faster energy regen and such, although I daresay mastery is better against clothies/leather due to EXTREME eviscerate crits, like really awesome crits, I done 21k!!
When using premed, you have 2 options, either to go recuperate for the energy regen OR OR OR OR OR premed > garrote > shiv > kidney > dance, that kind of works ok. I have also found that sometimes it may not be a good idea to wait such as long time before shadow dancing, due to the initial opener is when you have ALL your procs starting hence you can pump out much more damage. Heck, if your deadly serious you could premed recup, prep receup and do as said above.
Another thing to point out, would be if you are going for the kill and your on 20% hp with 5 combo points while your enemy is blinded, don't recuperate, Why? because you are going for the kill, it would be better to just Slice n dice > premed insted, the slice and dice is extremely helpful.
While playing with shadowdance there is alot to play around with, but any thing is that when you have blinded them, you can ALSO ask your self, when was the last time your random rng procs went off? Would it be best to sap 2 or 3 times to make sure that I will have these procs off when I am going for the kill.
I have probably missed loads, just let me know if I have.
hunter/healer (mostly discpriests): tunnel discpriest. just fucking tunnel him down, keep grounding out of range of your rogue behind your pillar, so you can ground freezing trap without the priest being able to sw: d it. with a druid, dont know. maybe tunnel hunter and oom the druid?
have your rogue ALWAYS sap one of them. pref. the one most dangerous, start purging the one your going on, or just prepare.
vs spriest/rogue: sap spriest, have your shaman run to him and purge before he gets a sap (he's gonna get one probably). resap until enemy rogue opens, then open hard on spriest. lust right away, help with purges on the priest. you should survive a rogue easily with ES on yourself.
vs mage/rogue: hard one. ES on shaman, sap mage i f possible. start purging him to get icy veins off later. no lust. stick rogue to rogue, so shaman can ghostwolf away and LoS some shatters. keep interrupting the mage with shocks, ground shatters.
totemstomping really sucks against a good lock or priest. its damn annoying, but at your rating he should be quite safe dropping it behind a pillar. if he sees a priest running to him(which shouldnt be the case, rogue always on priest) , have the shaman run away and frostshock priest maybe. keep dropping tremors. gcd is 1 sec for totemdrops
vs caster/healer its quite hard. mage/dpriest is a hardcounter, mage/shadow is very doable. just stick to the priest and outlast them.
mage/ele: stick to ele and shock mage. hex mage.