I do a lot of gluing and painting when working on my crafts. It can get pretty messy at times. My solution for this is to buy inexpensive paper towels and cut them into squares or rectangles (I cut several layers at a time) to keep on hand for quick clean-up of paint tips and glue tips. I store them in a gallon size zip lock bag. They can also be used to get your paint started flowing from dimensional paint bottles, eliminating globs of paint where you don't want them!
I save scraps from my sewing projects for the same thing- sometimes the material left over might just be a snip or two but it takes care of wiping paint bottles just fine.