Phone deleted intro page. It was really long. Anyways here's the how to part:

Step 1: What You'll Need

You can find most of this around your house (except the solder and iron)
1. Tape
2. Solder
3. Soldering iron (if you don't havef one you can just tape the wires together)
4. Cardboard
5. Cd case clear thingy
6. Some sort of switch
7. Some wire
8. A red, green, or blue led (they glow best in light)
9. Scissors
10. Some type of wire cutters (I'll just use some garden trimmers
11. Pliers (if you'll be ripping your led out of some circuit board.)
12. Cell battery (duh)
13. Swiss knife

Step 2: Cut Out the Body

Take your sheet of cardboard and cut out a rectangular box about the width of your tactical rail and however long you want it to be. Mine had a length of 3.4 inches and 1.3 inches

Step 3: Create the Sight

Ok, go ahead and take your Cd cover or whatever transparent material you got and cut it so that it will fit the dimensions of your box, once that's done, take your knife and etch a square (works best) in the center so you have a center now.

Step 4: Build the Circuit

Solder all the components together as shown in the photograph (I'm sorry if it's not understandable)

Step 5: Put Your Circuit in the Box

Self explanatory. If you choose a button switch make sure the wires are long enough and place the button on the handle of your gun so when you grip it it will turn on. If you chose a regular switch cut a hole on the side of the box and mount the switch there. Make sure you angle the led at the plastic etch. I taped my led on the same flap as the plastic and angled it straight up but you can do whatever works for u.

Step 6: Tape the Box Up

Also self explanatory. But make sure there is a gap on the top so the led can shine through and light up the etched plastic

Step 7: Finish It Up

Take your scrap cardboard and create a little shell over the plastic to improve visibility during the day. Tape it on and your done! If you like you can paint it with spray paint which I'm gonna do once I get some or ghetto it up with some sharpie coloring! Thanks for reading. Oh and to mount on your gun just tape it right on the center of your tactical rail cause I couldn't figure out how to mount it without losing accuracy. If it appears that the sight is too high up adjust the hop up on your gun until you get the desired results.