Dig a hole in the sand. The packaging or literature that came with your anchors will state how deep the hole should be. Most require a depth of around 12 inches.
Lay the anchor flat on the bottom of the hole, but keep a couple of inches of the straps resting on the top of the hole.
Cover the anchor with sand until the hole is filled in completely. While doing this, pat the sand down to pack it as tightly as possible. Again, make sure the top of the straps are a couple of inches above ground.
Run a tent line through the anchor loops and one of the loops at the base of your shelter, then tie a strong knot to secure the shelter to the anchor. If your shelter is homemade, you will need to create loops yourself, either by sewing them on or cutting slits near the bottom of your shelter.
Repeat a minimum of three more times to anchor all four sides of your tent.