the paper just started getting all wavey because of all the ink. How do I avoid that?
I'm fairly sure with that line of HP's printers, you have the option to change the DPI. If you drop the DPI down to a lower figure, the printer will use less ink, and you won't have an ink sodden cover!
usually in properties -> Advanced -> print quality
or somewhere similar. You may also find it in the HP toolbox thingy, if you have that installed