After the first week, you should have a well-behaved kitty. If you don’t, keep working with him and he’ll soon follow your instructions.
Once he’s done this for a few days in a row, put out his litterbox at each place where he goes to use it; then gradually introduce other places as well (for example: bathroom or hallway). Gradually increase the number of rooms that may be used as litterboxes if necessary. This can take anywhere from two weeks to four months.