Being fair skinned I have this problem out here in Mexico. I've found several solutions, here they are in order of effectiveness.
1. 100% effective- Foil at night. Obviously this has some disadvantages..
2. 95% effective - Foil only in the UK as for 95% of the summer it rains..
3. Very effective - two buffs, a cap, sunglasses and a long sleeved top and facestick. Downside is waterboarding after a crash especially whilst trying to keep the kite flying in light winds.
4. Fairly effective - Rimmed hat , sunglasses and lots of sun block. Needs topping up regularly as during crashes you are guaranteed to accidentally wipe some off. I tie the facestick to my harness.
In the winter here Im mainly on option 4, in the summer option 3
Best face stick I've found for me is Decathlon aptonia sun stick 50. By far the best for my lips. Zinc is great too but messy and more problematic on my lips.
We also came across an unusual subculture of kiters in Cuyo in the Philippines. They seem to have it dialled.
Jing and the Gang = No suncream required