Everyone should have their own philosophy by some point in their lives. Don't be a subscriber. Steal from other philosophies, but don't subscribe to them. Be your own philosopher. Have your own mind.
Here's a philosophy that people will preach: Man is a social animal -- you're meant to be social. Maybe there's some grain of truth in that, but don't believe it. Man isn't one thing or another. You make up mankind just as much as the next person, and you don't have to be social just because someone tells you that you're supposed to be, or that it's best for society in general. They say "we" developed instincts for survival and that one of them is to be "social." Well, "we" also developed you. Your survival indicates that mankind needs you, whether you're social or not.
That word "we", along with that word "mankind", are used in a general sense, taken (perhaps) from an average of us all -- the common denominator. Don't be average. Don't be common. Be the one-of-a-kind that you are. Have your own philosophy.