Everyone is bound to go down. So bring spare gear including gloves, boots, helmet, even a second suit, just in case you get knocked down. Make sure the bike can keep rolling too by bringing spare levers, footpegs, handlebars, even a set of spare take-off tires (what if you get a flat?), duct tape, oil, etc. Spares can be the difference between losing your entire day or just a few sessions.