The rules concerning business etiquette are often unspoken and sometimes hard to navigate. It can be tough enough to pick a greeting card with a sentiment appropriate for an office setting. Once you have made your choice, you now face the dilemma of how to sign it. What is considered to be "too personal?" Conversely, you have to be aware of the what looks too rigid and impersonal. There are no official rules dictating the way to sign a business card. But there are a few guidelines that you can follow to be on the safe side.
Sign your name. Do not use a stamp or pre-printed e-signature. Your recipients will be able to tell the difference. Take the extra time to sign with ink.
Include a short, handwritten message in cards that are going to important clients or business contacts. The best method is to keep it simple and general. "Best wishes" usually is a safe way to go. It can be related to the holiday season, (not Christmas or Hanukkah if you are unsure of the recipient's beliefs), new merger, acquisition or prospects. Unless you also have a personal relationship with the recipient, its a good idea to stay away from personal messages. Even something as general as "wishing you and your family the best" can unintentionally offend if the recipient is dealing with personal issues of which you are unaware.
Proofread your message. Typos are embarrassing, especially in a business context. Reread it yourself and then have another person read over it to make sure that everything is in order.