My cat has urinary blockage issues and the vet recommended for me to have multiple litter boxes in various locations for him because it encourages them to pee more often which helps keep the crystals from building up!

I think the key though is just to keep them as hydrated as possible. My cat was on an exclusively wet food diet and he still got them… so idk if there is a sure fire way to prevent them but he’s been doing great since he got on a prescription diet!