This is how to install legs on a Dragon Wagon. Remember, it is heavy so try to get a friend to help you.
Step 1: Stand the table up on its side (You can use a clamp in one of the side holes in order to get a grip/leverage, there is a GIF at the bottom that demonstrates this)
Step 2: Brace the table surface so it does not tip over.
Step 3: Put the legs on horizontally, starting from the bottom legs (make sure the holes line up on each leg across from one another). Torque the bolts to 30 ft. lbs.
Step 4: Stand the table up now that all legs are on. Remember, the table weighs upwards of 200 lbs - 400 lbs depending on the size, so be very careful (this is where your friend can help)
Done!