Determine which side of the tomato transplants faces the south. You must shield the tomatoes from the strongest effects of the sun on this side.
Drive one wood stake 2 to 4 inches into the soil about 4 to 6 inches away from each tomato plant. Use the hammer to pound each stake into the south side of the tomato plants.
Place the newspaper, cardboard or burlap against the stake to shield the tomatoes from the southern sun exposure. The piece of shield material you use should cover the area from the soil to the top of the stake, stopping at the point where the stake ends. This will provide shelter from the hottest southern sun.
Staple the shield material to the stake to keep it from blowing away, if necessary.
Use the sun shields for the first week after transplanting tomato plants outdoors. Remove the stakes and shields after this time.