ashleyblyth's Orange wedding

Ok so my fiance and I are very relaxed people, so our reception is reflecting that. The reception is not at some fancy golf course or hotel banquet room, but a simple new community hall that is large enough for 200 people and is surrounded by windows accross every wall. My only problem is that I am not one to know anything about decorating!! I need help! My wedding colours are orange and red! any suggestions on how to decorate a hall, make it look amazing, yet not overly formal??