Make a video of yourself. Have someone videotape you while in a tournament. Make sure you get the shot of your placement and trophies if there are any. Also, while making the video, talk about yourself, the types of things you like to do besides golf. If you are on student council, talk about reasons you are on there and things you hope to change. Discuss why you want to go to that particular college and what you can bring to the school's student body.
Write letters to the coaches of the colleges you would like to go to. Put your video that you made with it. If you are going to be in a tournament, invite them to come and see. Also, ask your coach or golf pro to write a letter of recommendation. Ask your coach to send invites to the colleges to see you in your next match.
Play tournaments outside your school during the summer months. Qualifying for bigger tournaments puts you up against top competition. These bigger tournaments are also magnets for college coaches, who spend the weekend recruiting players and evaluating talent.
Lower your handicap. Colleges look for as close to 0 as possible. Entering tournaments will be great practice and will get you noticed. Try to practice with a golf pro to pick up tips.
Stay in touch. If a scout comes to see you, write a thank you note. If scouts don't come to your first match, try sending another letter to your next one. They may have been busy for the first one. Thank them for any consideration they are giving you and always follow up with an email or letter.