make sure u have paint in yer loader whilst snap shooting in yer bedroom? mmmm i bet your walls are prettymake sure you have paint in your loader when practicising snapping. I also like to do specific accuracy, for example remembering where the light switch is behind the door. Helps when you switch, as you dont have to adjust as much.
Practice a game situation where you spend 7minutes with your gun up and shooting, reloading every so often, but making sure you have gun up for as much as possible. That stamina will help in the close cut matches.