Hi there. The other day I wanted to use one of my punches to make a card, and it was "sticking" to the paper, and therefore not cutting very well. So I had to find out how to "save" it. Here are two tips that I found to be very helpful for "sticking" punches, or punches that got dull.
How to lubricate your punch
Lubricate your punch by simply punching a piece of wax
paper. If the punch doesn't cut a perfect picture, it is ok. The wax from the paper is lubricating it.
Repeat the process as many times as necessary until your punch is no
longer sticking when punching paper. If THAT doesn't work, try to spray a little bit of WD40. Be sure to punch scrap paper to clean the excess before using on a good paper.
Sharpening a punch:
To sharpen your punch, punch a couple of times through aluminum foil or soda can.