Firstly, what is your experience with horses? Have you trained before? Have you ridden advanced mounts (i.e, horses that spook, buck, rear, bolt on a regular basis)
Training is a very time consuming process that requires a patient mind and a firm hand. If done improperly, the resulting horse can be dangerous and unpredictable. Improper training can also cause life-long mental and physical damage, and can in short completely wreck a horse. Improper training can also implant bad behaviors such as kicking, biting and rearing.
Even the most calm, quiet colt or filly can turn into a bucking bronco under saddle. It is very dangerous unless done by experienced persons who know how to stop bad behavior before they begin. An unexperienced trainer can end up dead or injured.
You need to know how to lay a strong ground foundation before you build the house. If your foundation is weak or incorrect, your house with fall.
I am very supportive of training your own horses. But sometimes, some things are better left to a qualified trainer.
Wait! I'll fix it....