How do you clean under your foreskin if you have phimosis?

It’s difficult. You don’t want to force soap underneath the foreskin because it can cause irritation if incompletely washed out. Instead, work on gentle retraction and with water in the shower and talk with a doctor about a topical steroid to help with stretching. Don’t worry — it’s not urgent but definitely worth doing for long-term ease of cleaning and sexual pleasure.