Snake skin will make you rich

Keep a piece of snake skin in your wallet if you want more money

This superstition is said to originate from Benzaiten (aka Benten), the only female deity of Japan's Seven Lucky Gods. She is the god of wealth and fertility, and snakes are her messengers. Consequently, the same power is inherited by snakes.

They repeatedly shed their skin in order for them to grow new skin. The shed skin itself does not regrow, but it contains the essence of growth which is passed to any money on your wallet.

You should also seriously consider having a shed-covered business card holder. Your visitor will be pleased to see you handing them your card which has been encased in snake's shed.

Verity:

Strike the last paragraph, since business cards are out of fashion now, largely replaced by some form of e-card. You could instead stick some shed to your iPhone, though I'm not sure any of its "essence" would be attached to an e-card.

The superstition's origin is said to be from Benzaiten. Actually she was one of the three major Indian goddesses, Sarasvati, the goddess of fine arts: music, painting, sculpture, dance and literature. These attributes help to soften the vulgarity of monetary wealth.

Rather than increasing your wealth, perhaps the only advantage of having a bit of shed in your wallet is as a talking point.

You could say "It's my lucky exuviae" if you can pronounce that word properly. And be aware that dead skin from any creature is not hygienic to carry around.

Final important note: If you're going to follow this superstition, make sure it's only the shed and not a live snake.