Easy enough, in the second mission of 'The Knife of Dunwall', once you have made it to Tamsh's home, her statue is on the top floor, the room at the end of the hall; or first door on the right if you come in from the patio.
The patio is the easiest way to do it, as you miss almost/all of the guards. Just follow the path behind the row of sport nets (9 and 10), and then blink up to the highest patio. Periodically there are guards there, so be careful. But once you make it inside her room, as long as you weren't seen, no one patrols that room.
Talking to her does not raise the alertness of any of the guards in the area, or change anything in the mission for you. So if you are stacking achievements don't worry about this changing your difficulty in any way.