This is almost identical to Level 3. Marco just need to turn right. Students need to understand that left or right are defined with respect to Marco's hands. If we ask Marco to turn right then Marco will turn towards his right hand. Therefore his new directions depends on where he was looking at before following that instruction.
The teacher can ask a student to stand up and play the role of Marco. Other students can ask her to turn left or right. This is an excellent way of visualizing the effect of the turning instructions.
The solution is similar to that of Level 3: