I don't use hot keys because I would always have to look down and find the right one. For BD, the best way for me, and the one I reccomend is to only use the Space bar. That pauses the game and from there you can use the potions you need, change weapons, and whatever else you need to use. That way, during an intense battle, you can keep a finger on the space bar, and your eyes on your screen. If you get low on anything or are almost dead, hit the space bar and drink your potions, or cast your spells. When you unpause, bingo, you are all cured up.