For filling nail holes in wood trim, or smaller holes in plaster, drywall and even plastic trim, a high-quality, lightweight, non-shrinking spackling compound is perfect. You can also use 3M Patch ...

Again, because spackle is so easy to use and remove, you have room to experiment without fear of permanently messing something up! Is the stenciling process a bit time-consuming? Perhaps ...

If you're replacing old trim with new baseboards, this is a handy way to quickly hide all the nail holes without having to spackle ... those, use a lightweight putty like Gorilla Wood Filler ...