I had the same problem when getting ready for my MOD2. So what I used to do was do a life saver opposite the way I was turning. So turning right on a roundabout , left life saver. All well and good I thought. Then I had one extra lesson before the MOD2 and this came up so I announced what I did and then the instructor, who was great, knew his stuff, and came across in a good manner and not a know it all pointed out one slight problem... Going straight on. You can go straight on in either the left lane or the right lane of a roundabout, so to me going straight on was a left turn, but if I was in the right hand lane my way of working it out was wrong. He explained it simply that you make the life saver on the area that you are not in, or the area on the roundabout where there is gap for another vehicle. He said that what your looking out for is cars coming up behind you in your blind area that you need to look for so that when you exit the roundabout they do not crash into you as you make your exit. Because you are so narrow they can try and get up the exit when your turning into it. Once he explained that it was simple then. So if I go over abound about, going straight on, but take it in the right lane, I would look over my left shoulder to make sure there are no cars coming up on me that may take me out. If I go straight on at a roundabout in the left lane, I would look over my right shoulder to make sure no car has come round the roundabout after I have entered that may exit my exit and come across me. That's how I do it anyway! But being only a 1 year old rider someone may point out a flaw in what I have said!