On the front of the business card, you can write: serve the people and facilitate everyone (the title is bigger, because it may not be registered by the company)
Write your name on a new line, bold and centered like other business cards.
Write down your address, contact number and mobile phone number below. If there is a fax, write it down, too.
On the reverse side of the business card, you can write: the content, scope and conditions of your service (referring to illegal things that don't serve). If you charge, I suggest you write down a small fee as appropriate and negotiate specifically.
These are my suggestions for your reference. I wish you smooth sailing and prosperity in serving the masses.