If you are a novice rider, please don't use draw reins. It is very easy to get a horse heavy on the forehand and trailing its hocks if you don't know what you are doing.
I certainly do not recommend tying a horse down or back to your average amateur.
Your horse will need to build up the strength to hold the collection. It takes time and you can not expect an overnight fix. Training aids have a place, but I strongly feel that a novice rider or your average amateur should not be using them without a trainer helping them.