Cardboard box- You want a cardboard box big enough to hold the items you're shooting. If you're shooting large products, you will obviously need a bigger box, so think about that ahead of time.
Box cutter- You will need a box cutter to cut the cardboard.
Poster board- This will make the seamless backdrop of our light box.
Tissue paper- We'll use this to create a "silk" for light diffusion.
Tape- Of course we'll need something to put it all together, so grab some scotch tape.
Cut holes into box.
Mark box using a ruler.
Cut squares into three sides of your box with the box cutter. Leave one side uncut to make the floor of the box.
Cut the flaps off, except for the bottom flap, which will also serve as the "floor" for the seamless.
Cut and insert poster board into box.
Measure and cut the poster board.
Slide poster board into the box. This will be your seamless. Let it curve without bending.
Then tape it to the box.
Tape tissue paper over holes.
Measure and cut tissue paper.
Tape the squares over the three holes on the sides and top. This will work as your "silk" and diffuse the light coming through the box.
Position the lights.
Next, you'll want to position the lights on both sides to get your desired effect. You might have to take a few shots with the camera and play around with the lights a little bit before you're satisfied with the image.