you drill holes in the pictures where you want the lights and poke them through from the back. We used a clear flexible caulking to hold them in place. Make sure you get it around the plastic, not around the inside of the socket. We put burnt out bulbs in the areas of the string that did not show. staple the wires down to keep them in place too. Make sure you buy the strings of lights that stay on when one bulb goes out. You may want to make a shadow box for these, so that the lights in the back don't show on the sides of the paintings. The little LED lights would work well or the smallest twinkie type too... sometimes it is fun to use two strings so that some twinkle and some don't. :D:D:D