Start at the bottom. Find an entertainment or talent representation firm and ask to work as a gofer, secretary, assistant, or any position where you can gain experience while completing mundane tasks. Many music managers got their start working as a gofer for established managers or individuals in the music business. Getting your foot in the door and having experience in the music industry is key to moving up in the ranks. The important thing is to take whatever you can get and never say no.
Find part-time work at a record label, no matter how small the job. Consider working at a music venue as a doorman or bouncer. Work as a student radio personality at your campus radio station.
Immerse yourself in music. Talk to the managers who come through your grunt job or the clubs and make connections. As you become familiar with and connected to musicians and their managers, you might set yourself up to become a concert venue manager or booking agent. The more familiar you are with music and the industry, the more appealing you will be as a business representative.
Go to college and major in business administration or management. This degree is perfect for music management when paired with music or music production as another major or a minor. Because so much of the music industry revolves around hype and publicity, taking courses in marketing might also be beneficial.
Apply for a job in music management. As you build experience at the lower levels of the industry, you make yourself better-qualified to obtain a full-time, salaried job. Finding a job can be difficult, so start early and be persistent -- you never know when your dream job might fall into your lap.
Get acquainted with up-and-coming acts in your area. Make them feel your interest in them. Let them know who you are and what your own goals are. If the musical group begins experiencing success, the connection you have built with them could lead to a job working as a manager or assistant.
Manage your friends. Most of them won't be able to obtain professional representation early in their careers. At the same time, loyalty can have strong influence in the music industry. If they do amount to something, odds are they will either keep you as their manager or set you up for future jobs with other bands because of the success that you led your first band to. At the very least, you will experience firsthand the trials and responsibilities of being a music manager in an industry where experience is one of your most valuable assets.