Normally a chain is whipped by passing the thread under the chain but this method of whipping is slightly different and also the final stitch resembles more of Stockinette stitch than Magic chain stitch.
Step 1 – Work a row of chain stitches.
Step 2 – Thread the needle with a second colour, bring it up as shown and whip only one side of the chain by picking up the loop from outside as shown.
Step 3 – Continue whipping till end and go back down.
Step 4 – Bring up the needle and thread close to the end point in step 3
Step 5 – Whip the second side of the chain stitches by picking up the loop from inside the chain as shown.
Hint : If the direction of whipping the second side is changed then you won't get the stockinette stitch effect.
Step 6 – Go back down near the starting point.