You can reward your contestants in 3 ways:
1.) Ranking Reward - allows you to reward the contestants with the most points. (Example: give a reward to the Top 3 winners).
2.) Point / Milestone Reward - allows you to reward contestants once they reach a certain amount of points or cross a milestone that you set. (Example: give ANY contestant a reward once they earn 25 points).
3.) Random Reward - allows you to reward a random winner based on the number of points they've acquired in your contest.
You can set up your reward method by doing the following:
1.) Go to your contest and click Reward.
2.) Click on the reward you want to edit and click edit on the right.
3.) Scroll down to Reward Type and choose from the drop-down menu which one you'd like to use.
4.) Scroll to the very bottom and click Update.