Set time apart every week to do an activity individually, such as planning a girls' night out or going to a museum by yourself, spending a quiet evening at home by yourself while you encourage him to hang out with his friends or do something that only he likes. It is good and healthy for couples to spend time apart. You may find that the time you do spend together will be more enjoyable after a little bit of absence.
If it’s at all possible I would look for something to occupy my time. This could be with a job, or a class or even a gym membership. Something to keep your mind busy while your boyfriend is unavailable. Being too cling will probably end up making him pull away from you. You will probably make him more interested in you, by spending some time away from him.
If you can determine why you’re clinging in a relationship, then you’ll find it easier to let go. Most of us hold on too tightly when we’re worried we might lose the one we love. This could be due to our own low self-esteem: we think we’re not worth their love and sooner or later they’ll discover the truth. This is a total fallacy and can be a self-fulfilling prophecy, so take steps to boost your own self-worth. You can do this by taking a class in something that interests you, spending time with people who value you highly (think friends and family), and achieving an academic or personal goal.
Clinginess could be the downfall of any relationship, especially with a guy who loves his independence. You should probably find more things to occupy your time, that way you'll think of the person less and less and not pester them as much. You should also set boundaries for yourself when you're in public with them. Keep reminding yourself and it'll sink in eventually.