I started a PC repair business a few years ago, and I can identify with and agree on many of the great comments.

My humble thoughts:

1. When marketing yourself don???t be shy about self-promotion. Drop business cards everywhere you go. Don???t rule out anyone as a potential customer.
2. Make sure you have a good web site. It doesn???t have to have a lot of info but it does need to look nice with good information. Don???t list prices on your site unless you are selling hardware, you want to take that call instead. Have easy to find contact info. There are several good companies to host your site with and easy to use templates to get started with. All consumers expect an IT professional to have a web site with an email address; preferably something that does not end with @Hotmail, or @yahoo. They are cheap and with the right wording you can list your company with the business side of search engines.
3. Don???t be afraid of competition. If a large company is bidding on a POS system or other hardware, services or development and you have the opportunity to bid, you should take advantage and do it. This is also a way to network and promote your business. You can consider some of the bids an education. But many companies like the personal interaction they get from smaller or owner operator businesses. Be sure to look around at another company doing what you want to do; someone who has a good track record. Look at their advertising look at their web page, check out their prices.
4. BE SURE TO BILL FOR YOUR TIME. Your work has value you should never have to apologize for charging a fair price for your service. There is nothing wrong with an honest profit.
5. Keep up with new technology. There are many online options for tech news and information.
6. Be sure you REALLY enjoy the area of expertise you have chosen. This will help keep you motivated if you enjoy what you are doing.

Jim