best way to prevent cauliflower besides wearing the headgear is to warm up your ear cartilage by rubbing them. If the cartilage is warmed up then it doesn't deform. I learned this technique from Kootch

You need to get it drained within 24 to 48 hours of the trauma (swelling). If you do not, it begins to calcify and once it gets to that state it becomes much more difficult to drain. In some cases they may put a wick in your ear, which might get some/most of the blood out, but the longer you wait, the more difficult it is to “cure”. There is a point where the only way to get back to “normal” is through surgery.