^^^ Agree with Sevrin above.
If you've been consistently camming on one site for a few years, you may get Christmas presents in the form of tokens from your regulars! It's a give and take though... you should probably give presents to your regulars too. You could make them a video or something.
If you're new, you might not fit into the "loved ones" category yet in someone's life, and at Christmas, people are generally saving their money for presents for their loved ones. So that's why some girls say December is their best month.... and some say it's their worst.
Last January I made practically NOTHING on cam, everyone was tapped out after Christmas. Be prepared for that as well.
Lots of other ways to make money in the adult industry, I find having your fingers into a bunch of things will help. When slow, try a different site, make a bunch of clips and sell them on manyvids or other clipsites, try phone sex, open an affiliate white label cam site.... options are endless.