In this video, This Old House landscape contractor Roger Cook shares three methods for laying out perfectly level lines.
1. Push wire ground flags into the lawn to mark the four corners of the building project.
2. Pound wooden grade stakes into the ground about 2 feet away from each ground flag.
3. Tie a nylon line to one corner stake, then stretch the line to the next stake.
4. Have a helper hang a line level onto the middle of the string.
5. Raise or lower the string until it's perfectly level. Tie off the string to the second stake.
6. To determine the slope of the grade, measure the distance from the level string down to the ground in three places: at each stake and in the middle of the string.
7. Add red food dye to a jug of water, then siphon the colored water into a length of clear plastic tubing.
8. Once the water flows from the opposite end of the tubing, let it drain for about 30 seconds to clear out any air bubbles.
9. Have a helper hold one end of the tubing against one stake. Take the opposite end of the tubing and hold it against the second stake.
10. Raise or lower your end of the tubing until the water level at the first stake is even with the desired height, then mark the water level at your end onto the second stake.
11. Without moving the water level from the first stake, carry your end to each of the remaining stakes. Repeat Step 10 to mark level lines onto the stakes.
12. Mount a laser level to a tripod and set it up in the middle of the four corner stakes.
13. Attach a receiver to a transit rod.
14. Stand the transit rod at a corner stake, then raise or lower the receiver until it emits a steady, audible beeping sound, indicating that it's level with the laser level.
15. Mark the bottom end of the transit rod on the stake, and repeat to mark the remaining ground stakes.