If you are evading the guards and need to get into Bruma, you will be arrested if you enter the main gates or castle, so use this cheat to get in without being spotted.

Go to the west side of the city walls and south of Cloud ruler temple, look around for a cave door called the Bruma caverns (note: if you have completed the main quest it will be on your map, and if you have already found it).

The Caverns lead into a house in the south western side of Bruma (note: you may also need some lock picks).

When you enter the cavern take the first right and follow the tunnel, there will be a door leading to the basement of the house.

There is a trap door to the house, it is above a few crates (note: if you have not completed the main quest, and done the quest where you enter this house, there may be one or two citizens, who may attack you).