Somethings to consider.
1 - decide what format of contest is for you. there are 2 types, A. - real money contests where you pay an entry fee and then another couple hundred for a live bankroll. You have to play like a minimum of 10 $20 bets. This of course means that it comes down to the players who are good , and have the biggest cahones. Check out Delaware Park contests on their website. In the last contest it came down to 2 fellows who bet ona $37. maiden, one bet $600 to win and the other $400. You are also playing vs, owners, trainers, agents etc. and you go home with whatever bankroll you accumulate and part of the purse too. - B - the other type is entry fee only and you make $2 win,place bets on a set number bets on say 3 tracks, with odds capped at 25/1. With no real money bet, you win a portion of the total purse.
2. only play in tourneys that payout all the entry fees taken in from entrants.
3. only play circuits you feel comfortable playing, I've played in NY, VA, Del. Wa. Did lousy in VA and WA . as I wasn't as familiar as local regulars.
4. play in a couple of each and see what you feel comfortable with. Choose smaller tourneys to practice in first, before taking on the top tourney pros in Vegas et al. There is a large learning curve to this type thing and to me its foolish to toss money away just so I could say I was in this or that big tourney.
5 - Good Luck !