[woodcote]

Yep, cut round with scissors or a scalpel. I use lukewarm water and soak for about 30 seconds, then gently see if the decal is released. If yes, good - if no, back in the water for another 30 seconds.

I also use Micro Sol and Micro Set...

   

Micro Set is brushed on to the surface where the decal will go - it softens the decal a little and helps you move the decal around so it's perfectly in position and gives a good stick, avoids bubbles forming and creates an almost seamless transition with the surrounding area.

Micro Sol is brushed over the decal if it needs to go round a large contour on the car or slip into panel lines, show rivets etc. The decal may wrinkle to begin with, but then goes nice :-)

Finally a clear coat over the top to protect the decals. I use Tamiya TS-13 Clear in a spray can, but it's always a good idea to test on a spare decal first - some clears can be too 'hot' for the decals and ruin them. Like with the Halfords paint, a few very light coats and then a wet coat.