Best case scenario, stop wanking just before you have a full orgasm. You will physically ejaculate, but without the full nut which causes you to not want to eat you own cum. A handful of cum tastes delicious.

Sorry for my unclear question, i mean ways to Interrupt an so it didn't happen. I Like to do it multiple times, so it feels more intensive. I searching for possibilities to get it more exiting.

I am not sure what you mean by a 'ruined' orgasm. Do you mean an orgasm that was interrupted and so didn't happen.. or wasn't satisfying?
Perhaps more clarity about what you mean will get you more responses.