Good question! Although you think this is a simple question, it's more controversial than you think. Some pediatric gastroenterologists think burping is a waste of time, but i always like burping, and it gives both the burper and the burpee a sense of satisfaction. My favorite technique: over the shoulder with gentle patting of the back. The nursery favorite: sitting baby in her lap with gentle back rubbing.
Over your shoulder. Especially if your baby is prone to spitting up or has reflux (gerd), place their belly toward your upper chest/over your shoulder and with a gentle, but firm pats of their lower back/bottom. This takes advantage of gravity pulling breast milk or formula downwards allowing trapped air to bubble upwards...And, hopefully, out - uuurrrp!