You don't signal when entering. If you are on the inside lane of the roundabout and prepare to exit, you signal to warn people already on the roundabout, and t

You don't signal when entering. If you are on the inside lane of the roundabout and prepare to exit, you signal to warn people already on the roundabout, and tell people waiting to get in that they shouldn't get on the outside lane even if it's free. If you are on the outside lane and prepare to exit, you signal when the road you'll take is next. Whether you'd personally wait is irrelevant; changing lanes and direction always warrants a signal, roundabout or not.