Printable plastic sheets are a good material to use for business cards. Plastic business cards won't easily get torn or crumpled. This resiliency could add to the good impression or impact you're trying to create when you hand it out to a client. Normally you'd have such cards manufactured by a printing service, but making your own is easy enough to do.
Design your business card.
What software you'll use is entirely up to you. Which programs are you familiar with? How elaborate or simple will be your design? The natural applications to use are graphics programs like Photoshop or Printshop. But you can actually also use something as simple as MSWord. Although it's essentially a word processor, you can still paste images on a document and use the Table function with non-visible gridlines to make a layout. Whatever application you may use, just make sure that you can set the canvass or paper size in both the design and printing stage. The common dimensions of a business card is 3.5 x 2 inches. Your final document should be filled with adjacent copies of your card so you can print several units in one go and on one sheet.
Purchase the plastic material.
You can find printable plastic sheets in office supply stores. A sturdy type of plastic and ideal for business cards is PVC or polyvinyl chloride. Width, length and thickness are dependent on your design concept but will be more likely defined by what your printer can accommodate. Printable plastic sheets come in a variety of colors but can also be transparent. If you're looking for a specific and uncommon material and color, you could search the Internet for plastic card or sheet suppliers. Some of them accommodate requests for specific dimensions and color.
Check your printer.
There are actually specialized plastic card printers that come with their own graphics software but this could be too much of an investment for something supposedly home-made. If you plan to use a typical inkjet printer, read the manual thoroughly and make sure you can actually feed plastic sheets into it and that the ink will actually stick. Take note that solvent-based inks are necessary for non-porous surfaces like plastic. Water-based inks need porous materials like paper for the printing to stick. So don't forget to check the type of ink your printer uses.
Print and cut out the business cards.
It was mentioned earlier that you can save on ink and materials by laying out and filling a sheet with adjacent copies of your business card. Consequently you're going to have to manually cut out each card from the whole printed sheet. To ensure accuracy use a cutting board with gridlines. You may also need to include very thin dotted line borders between the adjacent copies on the layout. These will serve as your guide when start cutting.
With the design and layout finalized, and plastic materials and printer matched, you can now start printing your own plastic business cards.