Regardless of what field you choose to enter as a freelancer, it is crucial to remember that you will need to create a portfolio, a body of work which can allow you to show others what you're capable of. Without this body of work, regardless of whether you're a programmer or artist, it will be virtually impossible for you to find quality work. Having a portfolio will also separate you from all those freelancers out there who say they can do this or that, but who don't have any actual evidence to back it up. Remember that the potential clients you come in contact with can't afford to waste time and money on someone who can talk to the talk about who can't walk the walk. They want to be sure you're capable of operating at a high level of skill “before” they provide you with an assignment.
This is why, when you are learning your skills and becoming more knowledgeable in your area of expertise, you must take the time to build a portfolio of the work you're performing. When this is done at the same time you're learning the skill, it will speed things up, because once you're done with the initial phase of your training, you will be ready to go out and find jobs and you will have a portfolio to show others. You don't want to build your portfolio after your training is complete, since that will take up more time, time that would be better spent building a client network.
The most important aspect of developing skills in any field you choose is practice, practice, and more practice. As my mother said when I was a boy, “practice makes perfect.” One key aspect of being a freelancer that you must understand is that the self employed freelancer must seek perfection, they must operate with a high level of accuracy and efficiency. Some of the clients you come across will be extremely picky about the quality of your work, and while too much of this on the part of a client makes them undesirable, you must always seek to produce superior work.
The only way you will be able to produce superior work is through an enormous amount of practice. We recommend setting up a schedule each week where you spend a few hours practicing your trade. While repetition may be tedious and even a bit boring, the skills that you are learning will eventually become second nature. One thing that should keep you motivated is the fact that you will face competition when you enter the market, and if this market is lucrative enough, the competition will be intense. You cannot afford to be lazy when it comes to your training. You must be better than the guy down the street if you want to build a large and lucrative client network.