joy-rick, do not, I repeat DO NOT use a razor blade to try and trim the lifted edges off your decals. You will scratch the gelcoat.
If your decals are still soft, you could use a silicone adhesive, but I have a feeling yours are probably lifting because of weathering and shrinking?
The other fellow with the 2011 and the lifting decal tips can definitely stick them back down. I also had a few lifting on mine, and the silicone adhesive worked great. And when/if the time comes to replace the decals, there won't be any damage to the gelcoat.