How do you access voice mail on your magic jack?

When I set up mine, all I did was connect it to my USB port, using the little extension cord included with the device. The computer recognizes and self installs necessary software. The internet must be on while this is happening. the program accesses the Magic Jack site and you need to give them credit card info, to charge you the 39.99-for the device, and 1 year of service. That's it.