I don't know about using a blood cuff, but you can do the same with a normal hand pump. You need a pump and ideally a tube that fits onto the pump and can be pushed into your bum. And then you just pump. You'll feel the air in your intestines. You may get slight cramps. If that happens, take a break until you feel better again and then carry on. What I can recommend is that you don't eat anything before pumping. You may have too much air in your stomach and then you have to throw up. Only pump yourself up as far as you feel comfortable with. With practice you'll be able to pump out more and more air.
2 months