Alan Henry at Lifehacker wrote a good piece for freelancers. Often people think that working for themselves will lighten the workload. It does, but it also introduces hurdles of its own.
Consider your work alone to be a startup. You are incorporated, so some things you don’t like to think about should be addressed: office supplies, home office, professional software, accounting, even the coffee and "break area."
Freelancing should be a good experience for the responsible designer. Professionals of all types are making more money, saving time, and taking their careers to greater heights while freelancing. Freedom lends itself to improved creativity.
There’s just a few chores to consider though. So tackle them if you’re committed to work for yourself. Be real with your expectations, and do things in good order. You’ll be thanking yourself later.