What about printing some labels and putting them the on the back of your biz card? Or getting some cheap biz cards and using those? Nothing fancy or colorful, just text.
Something like this
Thank you for purchasing my soap. There are a few things you can do to extend the life of your handmade soap. Keeping the soap dry is the number one rule. A soap dish that lets the water drain away is good. If the soap sits in water, it gets soft and gets used faster. Do not store in the shower where the spray hits it, the water will slowly melt it away. A nylon or bamboo puff helps too.
Something like this
Thank you for purchasing my soap. There are a few things you can do to extend the life of your handmade soap. Keeping the soap dry is the number one rule. A soap dish that lets the water drain away is good. If the soap sits in water, it gets soft and gets used faster. Do not store in the shower where the spray hits it, the water will slowly melt it away. A nylon or bamboo puff helps too.