You can either use the Trace function in the Glowforge software to create the image, or if you have a digital image of the business card (which most people use for printing) then you can get much better results.
The first method is easy, but might not get you the results that you want on something as small as a business card, the second method requires using external design software and there will be a bit of a learning curve if you are not familiar with the design software yet.
I’m going to point you towards some tutorials that are going to help you get started, but if you are already familiar with some kind of design software like Illustrator or Inkscape, just let us know what you want to use…there are “experts” here for most of the major design software.
First you will want to learn how to use the Glowforge interface…so reading through (and working through) the suggested examples are important steps for learning to use the machine:
Print a Gift of Good Measure.
Print a Snap-n-Store Box with Customization
Make a Gift Tag
Shortcut Keys
Working with Manual Settings
And the tutorial below expands on using the Trace function in the Glowforge: