P r i v a t e L e s s o n s . Private lessons are definitely the way to go to get an awesome start. =) They don`t have to be a professional, but definitely a better choice.
There are so many things that you need to practice on to improve on the clarinet. A private lessons teacher will help you out from the very beginning.
Method books are always a good start. Try doing long tones chromatically. Always practice your scales.