It's an ancient binding method used in Egypt to bind books. The main advantage it has over the other methods of bookbinding for perserving magazines is that with coptic binding you can open your magazines up flat. Which for hobby magazines is ideal. 
SWhat you need:

Awl
cover boards, I usually just use heavier weight paper for scrapbooking, a lot of times it's already the right size, but you can use chipboard and decorate it to suit your tastes, this is also a wonderful way to make mini sketch books. 
magazines to be bound
size 18-20 tesperstry/ribbon embroidery needle
heavier weight thread, I use my husband's heavy nylon for leather, hemp would work, something strong though. 

The covers are 2 seperate piece, the same size or just a bit bigger then your magazines, this book style leaves the "signatures" folds exposed. 

Start by placing them on each other and drilling 6 equally spaced holes in them about a half inch from the edge with the awl

Then you stack the magazines very evenly, and place the cover on top of the pile so the edge with the holes lines up with the fold/spine of the magazine, and draw lines with a pencil down the edges of the magazine

Open all the magazines flat and using the awl, poke holes through the center of the magazine where your guid lines are. 

Line up you first magazine with your cover board, and thread the needle with about 2-3 yards of thread, could be too much, but probably won't be too little. Bring the needle up through the inside of the magazine,leaving a tail for knotting, up through the top hole, put it in the hole on the cover, then bring it up between the cover and the magazine, and go back in the original hole you started in (sounds confusing, look at the diagram)
Dotted lines are inside.

Tie a knot using both the tail and the strand your working with. Bring your needle and thread up through the next hole, and repeat the last step. 

Repeat that for the rest of the holes on the magazine, when you get to the last one, instead of going back through the hole in the magazine, go through the bottom hole in the next magazine your adding.
Come up through the next hole, and loop it around the thread in the magazine next to it. Then back down into that hole, and up through the next one. 

Contine in that manner adding other magazines in the same way, when you get to the back cover, add it the same way as the first. 

Hope you enjoy this project!