As with all these designs, try to start with relatively clean, crisp bills. It will go much easier. All folds should be sharply creased. It helps to go over the fold with a fingernail on a flat, hard surface.

The spider requires five bills: four for the legs, and one to wrap the body.

(This is the first one of these I've put up with this type of image. I used a Casio QV-10A digital camera to get the images. I've tried to reduce the resolution of the JPEGs to the very minimum required to minimize your download time, but it is still quite graphics-heavy.)

Start by rolling up four of the bills into tight tubes (as explained here), then fold each one in half end-to-end.

Then fold the remaining bill exactly in half lengthwise three times.

Now you have the pieces.

Take each of the four leg tubes and drape them over the flat folded bill near the end. As shown, leave a little bit hanging out the end, as seen to the left in the picture.

This is a close-up of the four legs draped over the flat folded bill. While holding the leg ends tightly together, tightly wrap the flat bill around the whole thing one and a half times.

This picture shows the flat bill wrapping over and trapping the end poking out from the left on the picture above. Make sure that this wrap is very tight, that the legs are squeezed tightly together, or you won't be able to make the body stay together (described later).

This is a pretty good, tight wrap. If it doesn't look like this, don't continue. Work on it until it is solidly tight.

Fold a ninety degree turn into the flap over the end, and then fold the remainder down between the split legs. (Just look at the picture.)

After going between the legs (top of this picture), wrap the flap around the other end and around under.

If all has gone well up to now, the body will hold itself together based on the previous step. For each of the eight legs, bend back toward the body.