If you're not so steady with a caulk gun, don't despair. Lay a piece of painters tape on either side of the joint.
Lay your bead of caulk and smooth it out. All of the extra caulk will spread out onto the tape. Then peel it back and smooth the remaining bead. It won't matter whether your first bead was smooth or not - the tape took the beating!
The same concept will work if you're gluing a project too.
Hate filling nail holes because you have to sand later? Lay a piece of tape over your board before you nail. Nail directly through the tape. Countersink the nails and apply the wood filler right on top of the tape.
Let it sit for a few minutes and then carefully peel off the tape. You'll only have to deal with a little drop of filler.
Need to hang some drapery hardware, but finding it hard to work around the hardware. Transfer a template to a piece of painter's tape. Put the tape on the window frame and drill your pilot holes. Peel it off nice and neat!
Now that's putting painter's tape to work for you!!! I'm Mrs. Fixit and it's just that simple!