Lay out your wood pieces. The two long pieces (83 inches) will form the front of a tripod. The shorter piece (81 inches) will be the center leg in the back of the tripod. The 2x4 is the rack that will sit horizontally across the front pieces to hold up the painting.
Prepare the wood to be assembled. According to BuildEazy, you should use a saw to cut a new surface into the top of each front leg at 15 degrees. Drill to make the holes perpendicular to each of these new surfaces, which are measured at 78 inches from the bottom of these legs. Drill a hole through the back leg 74 inches from the bottom.
Assemble the legs. Lay them on the ground with the short leg in the middle and the angled faces on the longer pieces facing inward. Thread and secure a bolt through the top hole between all three legs, placing washers in between each of the front legs and the back legs in the center. Tighten the bolt just enough so the legs can pivot.
Attach the rack 2x4 onto the front legs. The placement height will vary based on the painter's height, but make sure the rack is attached as close to the level as possible. The 2x4 should be parallel with the ground. Once again, drill holes and thread bolts through washers in between the 2x4 and the legs.
Tie the rack to the back leg. Drill a hole into the back leg at about the same height as the rack, and tie a strong string through this hole and attach it to the rack. Before tying both ends, stand the easel up and measure a string length that will achieve a good angle between the front legs and the back legs.