If you're pretty enough to look good dressed and ready to go out, that's pretty enough.  Work on developing your inner personality for confidence.  Read books on the subject, go on line for opinions, do something in school that sets you apart, such as be good in art or the clarinet or help out in the office.  Always be helpful and nice to your peers and they will like you, too.  Keep your room neat so when you walk in at night or late day you don't get greeted with an unmade bed.  What a mood killer!  Neatness is worth it.  Redecorate, can be very inexpensive and fun.  Have a girlfriend help you.  Pick one who may need you a little.  Very good feeling!