Love 'em or hate 'em, you just can't get away from roundabouts. If you're learning to drive, it's a safe bet that you will have one or two "moments" while figuring them out.
Here's some advice on how to stay safe and become confident:
Let's start with a couple of basics - you can only go around a roundabout one way, and you have to give way to traffic on your right. Even these basics don't always apply, so watch out for traffic lights and signs.

People are often confused how to position on a roundabout. If you were approaching a cross roads, there are three ways you could go:
1 - Keep left to turn left (yellow)
2 - Also keep left to go ahead (blue)
3 - Move to the right to turn right (green)
Exactly the same rules apply at roundabouts. You join the roundabout at six o'clock, and treat any exit up to (and including) 12 o'clock as either left or ahead, staying in the left lane. Exits past 12 o'clock are treated as right turns, so use the right lane (until you need to move over for your exit).
No matter how many exits, the "12 o'clock" rule normally applies.
Many large roundabouts have multiple lanes. If there are no signs or road markings, use the normal rules.
Lots of big roundabouts will have signs and road markings to guide you. So you have to know where you want to go! Follow the lane marked. Look for signs and road markings.

- "What if I get in the wrong lane?" - Don't panic! If it's safe, and there's time, simply move into the correct lane, gving a signal if necessary. If it's busy, and not easy and safe to change to the correct lane, simply follow the lane you are in. You will end up going the wrong way, so find somewhere safe to turn round later on. Better late than never...
- "I never know who to give way to at mini roundabouts" - Well, you're not alone. Like bigger roundabouts, give way to traffic on your right. Traffic on your left should give way to you.