I have had probably 150 Strapon type sessions. I actually learned this from a shemale who when I asked if it work she replied, “ I am inside the guy, I know how it feels and what works and what doesn’t”. Here you go.
Go get a saline small enema. Open up and unscrew. Pour the contents out and rinse it out. Fill with warm water and put top back on. Get close to toilet. Lay on your side, insert and squeeze hard. Immediately get on toilet and evacuate. No waiting. Flush toilet.
Clean off tip, fill again and repeat. If the toilet is clean after the 2nd time so are you.
It has worked great and because you evacuate quickly no liquid stays in.
As the shemale added. I am just trying to F a guy, not give him a colonoscopy. I will never do it another way again. Simple.