Dowloading my pictures from my camera onto the computer?

My camera is a Nikon D3100. Can you please tell me what i have to have and step by step what to do to download my pictures from my Nikon onto my computer? Please help!

Added (1). I have the newest generation of an Apple computer btw

Apple isn't a wise choice since 95% of the planet runs on Windows - but then only 95% of the world shares my opinion.

Most of us regulars here use and recommend usb card readers for (upload by the way). They're not expensive and are available where ever cameras are sold.

Here's a link that might help you!

And although I have 5 windows machines, I also have 2 Macs.

And regardless of what someone might think, Macs are probably used by about 50% of the creative community. Most of the writers, who are also pro-photographers, for Shutterbug use Macs.