Looking for a cheaper portable LED light for on location filming or photography well this is the $20 light. First you will need the items in the photo below. The poster board was $2.50 the wire was like $6.00 and the LED light strip was like $8.00 on amazon free shipping. Now I had all the tools if you have to buy the tools then this cost you a little more but not much. If you do have to buy the tools and battery holder then it might cost around $35.00
Step 1: Poster Board
Decide what size you want your light to be and mark the poster board with your favorite marking tool. I am going to base this off the size I made my light so I made my board 14"x 11-1/2" . Then cut out the poster board with a razor knife be careful not to cut your self. After you have the board cut out measure 1" make a line parallel with the 14" side then space you lines 5/8" apart. The draw lines parallel with the 12" side 1" inch from that side on both sides. These lines are to keep the LED strip lights straight.
Step 2: Cut LED Strips
The LED strip lights have cut marks on them with a picture of a pair of scissors be careful to cut as center of that mark as you can cause it will determine how much area you have to solder too. So cut the strips at 12". With the roll of lights I purchased I got 16 strips.
Step 3: Trim the Gel Off
The LED strip I have are water proof so thy have a gel cover you have to get this off the term points to solider. I used a razor blade to cut into it but not all the way just go about half way then peel it off this can be a little cumbersome but it doesn't take long.
Step 4: Glue the Strips
Next you need a hot glue gun I started with the first line and ran the flu just under the line. Then peel the off the paper from the back of the lights strip and put the strip on the glue pres down evenly as you move down the strip keeping it lined up with the line. And do this for all the strips until you are done. Keep in mined the glue can be very hot and try to put a then line of glue also try not to get the glue on the front of the led strips it seems like the rubbery stuff on top of the lights is the same stuff that the glue is made of so the glue can melt it.
Step 5: Cut the Wires
With your wire cutters cut little strips of wire about 1-1/2" long your gonna need like 32 of them then strip the end about 1/4" off each end. Then get your solider gun heated up and tin all the ends of the wires with solider. Next tin all the ends of the light strips with solider.
Step 6: Solider the Wires to the Strips
So now you need to solider the wires to the lights. I wire my lights in series all the way through I tried doing half and half in series then in parallel to see if the lights got brighter but it did make a difference so I went in series. I drew a picture so you can get the idea if your not sure what series means. At one end you will need two long wires for battery hook up you can put what ever type of connector you want I don't have one on at the time but I plan on putting a connector that will plug into a rc lipo battery
Step 7: Power It Up
Turn on the light. I also made a red one.