Start by using your utility knife to cut the front of the cardboard letter off. Insert the knife tip into the side of the letter, as close to the front edge as you can without going over the edge to the front itself, and cut. Once the entire front of the letter is open, remove the inner lining from the cardboard letter.
Next, apply a coat of paint to the inside of each letter. You may need to use two coats of paint to make sure your cardboard is all one color. Set aside to dry for about 1 hour.
Once the paint is dry, sketch out where you want your lights to go by using your pencil to make a circle on the back of the letter where each light will be placed. The circles should be about the size of the bulbs on your string of lights, and equally spaced apart. You will use about ten lights per letter, so you should have ten circles. Use your ruler to make sure the circles are evenly spaced. A good rule of thumb is to place them 4 inches apart, though this may vary with the size of your letters and the number of lights you have. These circles will give you a rough idea of where each light will go.
Repeat the previous steps for each additional letter you’ll use in your sign.
Next, lay out your word painted side down with the letters in reverse order, so that it reads from right to left. Use your utility knife to create X-shaped cuts in the center of each circle you sketched on the cardboard. These holes should be big enough to fit the socket of the light through, but not so large that the bulb will fit through.
Remove the bulb from the first light and push the socket through the hole you made. Once the socket is through the hole, lift up the letter and screw the bulb back on from the front side to secure it. Unless the letter you are making is straight up and down, like an “L”, while looking at the backside of the letter you want to start adding your lights at the bottom right of the first letter in the word, go up and around the letter, and end at the bottom left of each letter. This will make it easier when switching to the next letter, since you’re using the same strand of lights.
Once the lights are fastened on each letter, your marquee sign is complete. If desired, use thumbtacks to hang it up on your wall near an electric outlet so you can plug it in.
Excerpted from <a rel="nofollow" href="http://www.amazon.com/gp/product/1440588023/ref=as_li_tl?ie=UTF8&camp=1789&creative=9325&creativeASIN=1440588023&linkCode=as2&tag=craftfocom-20&linkId=C24LPYJKJHCXNL2H">DIY Bedroom Decor: 50 Awesome Ideas for Your Room</a>. Copyright © 2015 F+W Media, Inc. Used by permission of the publisher. All rights reserved. Photographs by Tana Smith and Debby Wolvos.