Unfold and spread the inflatable lawn decoration on the ground. Choose a location that is away from overhead power lines and tree limbs that can cause damage.
Locate the anchor tethers attached to the base of the inflatable decoration. Place a ground stake in one anchor tether and drive it into the ground with a hammer or mallet.
Move to the tether opposite the one that was just secured and anchor it to the ground with a stake. Continue working around the inflatable decoration until the base is secured.
Inflate the decoration as instructed by the manufacturer. Typically, this involves the use of a small blower to inflate and maintain the shape of the decoration.
Secure tie-down lines to tether points positioned higher up on tall decorations. Tie the line to the tether and pull the line down and out away from the inflatable decoration. Drive a stake into the ground and secure the tie-down line in place.