JoAnn's sells rag quilt snips. They are AMAZING!!!! They are spring loaded as someone else suggested and saved my hand muscles. I snip after everything is sewn. I leave the quilt on my ironing board and tell myself "I'll just snip a square or 2 every time I walk by." Usually end up snipping a whole row. I save the snipping of the outer edge for last as it's only 2 layers vs 4. I like to snip the 'intersections' first as they can be the most troublesome.
They really are an amazing tool!!! I went out and bought quite a few when I found them. My children saw me 'having fun' and wanted to help snip too. With all my extra snips, they could join me. The only thing I asked them was to tell me if they snipped through any stitching. It's a lot easier to fix prior to washing than after. I assured them that even mama snipped through the stitching from time to time and I'd rather them help and tell me, than not help at all!