With my regulars they will just do it in the heat of the moment. It's worth finding a girl that is beautiful and finds you attractive. Build the trust and it happens organically. And it's usually free at no extra charge.
Some girls have offered it first up at a cost of 3 to 4 pineapples. I stupidly accepted those offers, but now won't do bbfs at firs offer as the risks are too high. If its offered early on then they are doing it with others for money.