Solar post lights install very easily. Simply attach them to the side of the posts on your deck railing with ss screws. When you are deciding which side of the post to attach them to, keep in mind the position of the sun.Solar deck lights will need to charge throughout the day, so be sure the solar panels will not be shaded by the post.Solar spot lights are another popular deck lighting choice. You can attach these solar lights directly to the wall or hang them from the eaves of the house and when the sun goes down, the lights turn on.Post caps are possibly the least obtrusive solar deck lighting option around. After you measure your deck posts, you should be able to find solar post caps that will fit right on top of them. Just set the caps on top of your deck posts and screw them in so that they stay secure.