Article: Use scrap boards that are about 1 foot (0.30m) long. Nail them into place so that they go up over the edge of the floor. That way, when you're lifting the walls up, they won't slip off the platform. While there are ways to do this on your own, the easiest and safest way is to grab another person to help. Brace the bottom against the pieces you nailed into the floor and swing the top edge up, walking it into place with your hands. With a drill, screw through the bottom board in the frame of the wall into the floor below. Use at least 2 3in (7.6cm) screws between each vertical stud (board) to hold it in place. Make sure you leave even spaces on both edges of the back wall to slide the sides in. Go through the same process with the other walls, starting with the sides. After screwing in the bottoms, screw the sides into the back panel, too, placing a screw every 1 foot (0.30m) or so. Face the right angle of the triangle on top to the front. That way, it will meet the front wall. Once you're done with the sides, do the same with the front, screwing it into place.

What is a summary?
Nail 2-3 small wood braces along the floor on each side. Ask for help to raise the back wall and nail it in place. Screw the wall into place at the bottom. Raise the other walls and screw them in place.