Many college coaches will want to see a video of you in action. Coaches rarely recruit an athlete sight-unseen. Especially with team sports, have a video of your championship play available to send to coaches on request. Coaches spend summers coaching at camps and interacting with high school athletes for the purpose of recruiting. Many future college players are discovered at summer camps.
Most coaches run camps on their campuses.
If they're not running one, they're working someone else's. It is highly recommended that you attend camps where college coaches will get to see you play. Not only will coaches get to meet you and watch you play, but you get to meet the coach and experience that coach's philosophy and techniques. Coaches can not possibly see every athlete compete and can't possibly know about every great athlete out there. Some college coaches get recommendations from club and high school coaches.