You need one sort of yarn in two contrasting colors ( A and b) and a matching Tunisian crochet hook.
1. Ch as many as you want to in color A.
2. Pull loops through the chs in color A. (see First Row in Tunisian Simple Stitch)
3. Go back with color B.
4. Start new row with color B. Pull loop through first vertical strand just like in Tunisian simple Stitch. Second one is done like in Tunisian Purl Stitch (let yarn fall before you insert the hook, see Tunisian Purl Stitch).
5. Go on *simple st, purl st*
6. Don’t forget to insert under to strands at the edge.
7. Go back with color A.
8. Start new row with color A.
Go on and on until you have your desired piece of crochet work.
Have fun crocheting!