Do have business cards that include your name, contact information, doctoral status and, if applicable, list your master's degree, research interests and Web site.
Don't ask directly for a job. Instead, say you are looking for opportunities or career advice and ask if they have any suggestions about people you should contact.
Do keep track of the people you meet, such as by creating a filing system for business cards and contact information.
Don't be over the top with your flattery of the other person. People know when they are being snowed.
Do dress professionally, make eye contact and use a firm handshake.
Don't be intimidated by a title or reputation.
Do send a thank-you note if someone has helped you. It's a turnoff when someone spends time answering your questions and then receives no acknowledgement.