This is all you will need to get started, plus your computer and a printer for the template.
Print out the two templates from http://mashable.com/2012/10/13/cardboard-laptop-stand-diy/ on regular A4 paper.
Place the template on a piece of cardboard and trace it with a pen. You will need the triangular shape twice and the long rectangular piece three times for your stand.
Cut out the five shapes with your cutter or a big pair of scissors.
When you have cut out out all pieces, use the three connecting pieces to connect the two big pieces at the little notches.
Ta-daa, it should look like this!