I have recently gotten into 4x5 large format, and while I was waiting for my film to arrive, I cut down some 8x10 paper so I could practice some shooting. I have been contact printing these paper negatives on some 5x7 paper, which looks really nice. The problem is I can't get the negative to sit straight on the paper when I place the glass on top. (I don't have a printing frame, I am placing the sandwiched paper under glass on my easel and using the easel mask to define the print.) Somehow, it always moves... sometimes only a little, sometimes a lot, but whenever I print, the image is always a little bit off that perfect alignment.

This is extremely frustrating. Is this just a problem with paper-to-paper printing, or can I expect this same frustration when I start printing my film negatives as well? What do you do to keep your prints/negatives aligned?