Wear fashionable clothes. Looking good will get their attention and attract them to you.
Smile! Everyone is drawn to smiling faces, and smiling shows that you are friendly.
Meet that one friend. If you see someone that really looks like a great person or someone you want to be friend with, just smile and say hi.
Start a conversation. Ask people open ended questions and remember to listen before speaking back. Never speak at a friend, speak with them.
Meet the friends of your new friend. If you make a couple of friends, they probably have other friends as well, which is a great opportunity to get to know a whole group of new friends. Eat lunch with them or hang out after school. Also if one of your friends is part of a "gang" try to find out interests you all have as a group and put emphasis on those topics rather than drive away from them.
Play around and be open. If you're friends are in a club or sport, why not try it out? You don't have to stay with it forever, but you'll never know if you're missing out on a great time to hang out with your friends if you don't try. Invite them to your house, go to the pool with them, take them with you if you go out for lunch or shopping, and look for any reason to hang out with your friends. But don't take it personally if they say no!
Select the person you would like to be best friends with. Make sure they do not already have a best friend because you don't want to make any enemies.
See if they are in any of your classes or clubs.
Talk to them. Do not be annoying! People hate people who cling on to them.
Ask them if they have a face book and if they do then add them.
Talk to them online and in person more and more.
Invite them over for a sleepover or to go see a movie.
Ask them if they want to go to a party with you
When your birthday comes, invite them to celebrate with you.
Make sure to always listen to signs from them, to make sure they want to be your friend still.