Since a horse trainer is self-employed you can choose what you want to study for this area.
Others may attend a four year university and major in Equine Management or Equine Business.
A typical Day (Jockey)
Around 6:30 AM they work the first of many horses assigned to them that will be running in an upcoming race. They have to constantly check their weight to make sure they aren't over weight for the horse they will be riding. Then the weight of the saddle and girth is checked and recorded by 11:00 AM. By 12:30 PM the first race starts and they get done around 6:00 PM.
range of salary
Wisconsin (Milwaukee area average): $47,722 (professional), $17,580 or less (non-professional)
In Kentucky the demand is higher because of needing trainers for the race horses. There your job will be more stable and promising where you will make more money and it will be constant working.
Depending on where you live you wont get paid as much as somebody training a race horse. You also have a high risk of injury, which if you get a bad injury you will be out of work for a while with no income for the period of time. If you aren't a professional trainer then there's a chance where you will have to get a second job because you won't make enough to support yourself.
Some trainers start out as groomers, help out around the stable, exercise horses, and feed. Equine trainers have to find many ways of training horses because each one responds to certain ways differently. Most trainers need to look at the horses nutrition/feeding habits and health. Most trainers go into a specific discipline such as eventing, dressage, racing, gymkhana and reining.