It took me about a month to teach him that (he was about a year and a half old). I started off by sititng on the floor with him, rolling him over gently, rubbing his belly and softly saying "Show me your belly". Then I would roll him over, say it then rub. Little by littly he started to get it. Believe me though, he is still a basenji and does not do it every time. :D I would say he does is once out of maybe 3 times.