“Cum no her tits”
That’s how it should be taught. Because you can’t get a girl preggers if you jizz on her tits, on her face, in her mouth, or up her butt. So you can suggest abstinence (it is 100% effective, except that noone does it), tell folks to use condoms and pills, and always keep in mind that you can just pull out – but don’t wait until the last minute. Pull out early and do the final stretch (heh heh) while you are outside of her puss.
tl;dr – Fill her belly button.
Or like… jizz on her back. Anywhere, dude, just not up in them guts. Really. Though if you want to be a gentleman, you should avoid the hair.