Just like a traditional intersection, you need to be in the correct lane, and signal the direction you are traveling whether you're turning right, left or going straight through. But, unlike traditional intersections, when you exit a roundabout you need to signal right to indicate you're exiting.
To keep traffic flowing, roundabouts are designed so that lane changes aren't required once you're in the roundabout.
Turning right in a two-lane roundabout:
Going straight through a two-lane roundabout:
Turning left in a two-lane roundabout:
If you need to make a full circle (u-turn):
These are the general rules for two-lane roundabouts, but it's important to always follow the lane designation signs and pavements markings as each roundabout can be a bit different.
For example, the roundabouts at 67 Street and 30 Avenue and 67 and Orr/Johnston Drive have dedicated right turn lanes, meaning you don't have to enter the roundabout. Simply signal right, follow the right-turn lane and merge with traffic exiting the roundabout.
These roundabouts also have a unique feature called spiral lane markings, which are used to accommodate the double turning lanes or to position you to exit the roundabout easier where there are accesses close to the roundabout. While modern roundabouts are designed so that lane changes are not required once you are in the roundabout, the spiral lane markings will guide you from the inside lane to the outside lane in some cases - when you do this you are not crossing lane markings, and thus not making a lane change. This makes it extremely important for drivers entering the roundabout to yield to all lanes of traffic already in the roundabout.
Specifically this occurs when: