Passes are another type of "money" on howrse. Everybody loves them, everybody wants them. You can buy passes by calling howrse or by using paypal. If you cant do those things then try these ways to get more passes.
1). You get 1 pass for every 5 Karma points acquired
2) You get 1 pass every time 5 of your sponsored breeders reach the 8th Riding Level
3) You can get 1 or more passes by selling a horse against passes in the private sales.
4) You get 1 pass if you send a horse (over 30) to heaven.
5) On your 50th day, you can purchase 1 pass with money from your reserve (20% of your reserve)