I put the decal on an area of the kit where I've just applied Microset, put it into place (sometimes having to use copious amount of Microset or even water), clean up the mess with a piece of kitchen roll, then apply a small amount of Microsol near the decal, letting the capilary action move the liquid all around the decal.
Microsol softens the decal and will give it, at least temporarily, wrinkles. It is a stage when touching, relocating the decal is dangerous because the carried film is really becoming soft so that it can adhere to all recesses, and other bumps the surface of the model features.
I only use Microsol/Set on difficult surfaces. On flat and easier surfaces I onlu use a bit of Klear/Furure as a wet bed for the decal, then using water/saliva to clean up afterwards.