how to deal with an 8 color watch?

Hi Forum, I'm new.

I'll try to answer this - a bit late to the game but it might help some new devs.

8 colors means black, white, red, and 5 more. There is no gray (while you still might simulate it, later more). So, double check you don't use anti-aliasing in your fonts. I find it easy to simply store my fonts in a monochrome version. That also saves some memory. These monochrome fonts are then used for those monochrome displays as well as the 8 color and 14 color displays.

You could simulate and gain different colors if you iterate between two colors, pixel by pixel. I find it easiest to draw the text in one color, and then write a checkers pattern in the background color over it. That might provide a different effect.
Otherwise, you could try to create a copy of your fonts, where also only every second pixel is black. After rendering your text in one color, you could use that font to "mix" another color into the picture. But that's not tested. Might look okay, maybe even cool, but probably bad. Leave some screenshots if you try.

Good luck