Long run - taper. Drink sufficient fluids for long runs (drink at least every 30 minutes) and ensure your body has enough electrolytes coming in either through electrolytes in your drink or gels or other form. Eat gels for energy and practice eating gels as you would during a race to nail down your plan of quantity and timing for gels. This will also enable yout to see how your body reacts to gels and hydration prior to race day.