You should wear your OA sash normal and MB sash on the waist. This is how my troop does it. And, to those who are saying the OA sash should not be worn at a non order function, WHY? I believe that if you earned it, you should wear it. It is an honor to be chosen and it should be worn with pride. It is in accordance with the BSA and therefore should be considered part of the BSA uniform. Its the same as rank patches or merit badges. You earned them, so wear them. If that is not what the OA book says, mine is not with me, then something should be done about it. That rule should be changed.