Learn as much as you can about the game. Read the all the help pages in the Hooves of Fire Wiki. Take a look at the forum once a day and use in game chat to ask other players questions.
Becoming a VIP (US $5 a month) provides a lot of additional features such as the ability to sell horses, access to the science lab, boosters and steroids, custom saddles as well as a further insight into your horses ability and what tracks they like.
The Hooves of Fire Racing Club is a Facebook group that anyone can join and post information about their stallion they are studding or any horses they are selling. Players can also post tips or give advice about the game, ask questions, write about their horses and what they have achieved or discuss anything else about the game.