What can i do to get rid of this? HELP!?

ok well i have a little lisp and its so small that most people don't even notice it until someone else that already knows about it points it out. i hate it though i feel so self conscious when i talk and use words with letters c, s, x. i don't get teased about badly my friends just mess with about it but i get embarred about it and don't wanna seem like a baby. but anyways is this anyway i can get rid of it with out having to take like a speech cl. does anyone know of like an exercises i can do or a video i can watch to get rid of it??