For any basic learner of a new language it is highly advantageous to follow classes to avoid developing any bad habits. That being said, as a teacher my clear experience is that the individual student's willingness to do hard work makes all the difference. Classes and a lot of self study is clearly the best option. A good course will provide you with ample material for self study.

Look through the sites offering classes and find which method will help you the most in learning Norwegian.