My husband had to take a photo of something against a white backdrop at home the other day and being the resourceful guy that he is, he decided to make his own light box. I couldn't believe how easy it was to make and how amazing the photos came out. For someone like me starting their own Etsy shop, this is a great way to take professional photos of some of my smaller items I'm going to sell. Also, it's just fun to play around with.
As you can see in the photo above - it's pretty simple. You take a cardboard box and cut away the top and sides. You then tape the white tissue paper to the top and sides. To get the "infinity background", you just need to attach a piece of white posterboard to the back of the box and make sure not to bend it. The curved background makes the "infinity" effect.
Obviously when you take the photos you need light so you just need to make sure you have light (such as two lamps) positioned on either side of the box. Also my husband pointed out that you should have the lights out in the room (and just the lamps on). And don't use a flash when you take these photos.
Here are some photos I took with my iPhone 4s.
Here's a link to another tutorial online that has more specific instructions and tips.