MMS,
The biggest factor in a general sense of contentment is to create a scenario for yourself where you have 'something to look forward to, and someone to share it with.' The 'someone' can be a mate, a group of friends, teammates, a personal relationship with God, or any combination(s) of these. I would add that always striving to be "in the moment" and the satisfaction of doing "extremely well" the things you do, can be fulfilling icing on the cake.
Throw yourself into your activities, studies, recreations - exert maximum energy into everything you do - and while you're busy laughing and striving at all of those things, the person/persons you need will show up and hold close your heart.
When you feel sad, examine it, learn from it, but don't be taken by it.
All my love,
