There are a few ways to do it, but in general just eat and rub a few times, while oinking, and keeping doing all that until it triggers. I softened some requirements.
If I remember right you must do it 10 times combined, where oinking counts as 0.1 or 0.15 times, while eating or rubbing as 1. There are some base requirements of doing each action a few times at minimum, but I made it much lenient recently, and also gave players more time. Hopefully this helps!