Buy some nice card stock for your business cards. Depending on what your printer can handle, business cards that you print at home should be about 14 point.
Make sure you have a decent photo printer. Do a test run of printing to see if the business cards look good.
Download or buy some business card design software. You can also get templates to download online. When you print business cards from your computer you have to decide how much flexibility you want. There are some great templates online that might be enough for your needs.
Design your cards on your computer. Remember that good business cards let clients and suppliers know exactly what your business is about just by reading your card. Leave off your address but make sure to include your phone number and email.
Once you are done, you can go ahead and print your business cards from your computer. do a few designs if you want to see what looks good.
Use a paper cutter to cut out the business cards. Some people like to round the corners for a cool effect.