Never really looked at options for printing a Google calendar, but they do look rather limited. I’ll offer some guesses, but can’t say for sure either of these would be any better.
My first thought would be to just display less on the screen and use multiple screenshoots to create images of each “page” the way you want it to print.
If that doesn’t work, then I’d consider exporting the calendar and then importing into Microsoft Outlook on the PC or the Mac’s Calendar program to see what things look like there (here’s the somewhat convoluted export process: https://support.google.com/calendar/answer/37111). I don’t know for sure if this will work and guess you may have to re-color code things again, but you could check the calendar programs available on your computer to see if things print the way you like them. If they do, then try exporting what you’ve already created into Google (or if you can view the calendar in your calendar program).
Sorry to not have an easy answer, but maybe some of those ideas will help.