Techniques for deep rough around the greens is much like a menu, lots of choices-

1. Use a SW rather than a PW or LW rather than a SW
2. Ball position could be left heel as opposed to middle of your stance
3. The face angle could be slightly open or a lot open depending on the pin location
4. Speed of the swing on way thru could be 35 mph from a thick lie as opposed to 20 mph from a good lie
All the best with your choices, and remember, if the lie is really thick, you could choose all four !