How to make a silicone ass

Hi,

I would like to know how to make a silicone ass. I understand that I need to have one first, make a mould of that, then pour the silicone into the mould that I would have made. In a nutshell is that about right? Of course with many more steps then that to make the mould itself

Or an easier option, buy the mould, but where the heck can you buy a mould of a silicone ass? Iv looked high n low all over the internet, unless im using the wrong keywords.

any advise would be appreciated