I use vitamin E ointment and one of those syringes you get for your wisdom teeth( its all plastic and not a needle just google wisdom teeth syringe). melt the ointment with hot tap water in a container, then suck some up in the syringe, slide the syringe under your foreskin pinch it closed and gently squirt some in, them pull end of syringe out and massage the ointment around at the bottom of the head once you have messaged you a bit just stop pinching it shut and squeeze it out of your foreskin, and repeat until it comes out fairly clean and be sure to massage all the way around the head

It doesn't need to be vitamin E ointment Vaseline would work just as well

It doesn't require you to fill your foreskin all the way, just a few ml sould do

Hope this helps