Summarize this article:

The traditional way of joining Freemasonry is to ask someone who is already a member. If you know someone who's a member, let him know that you're interested in joining, and tell him you'd like to petition for membership. He should direct you to the appropriate venue to issue your petition; you'll have to answer some questions about why you want to become a member. If you don't know someone who's member, there are a few things you can try: Look for a "2B1Ask1" sign. You'll see this on bumper stickers, shirts, hats, and other items displayed by Freemasons who want to welcome new members. Look for the Masonic square and compass symbol. This is a bit harder to spot, but you may see someone wearing it on a t-shirt or another item. After you've submitted your petition to a particular lodge, the Freemasons there will review it and decide whether to invite you in for an interview with an investigative committee. If they wish to call you in, a date and time will be arranged. During the interview, you can expect the following: You'll be asked questions about why you want to become a Freemason, and you'll be asked to describe your life story and your own character. You'll get the opportunity to ask them questions about how things work at the Lodge. After the interview, the Freemasons will conduct an investigation into your life, which will include calls to people close to you who can verify that you have a high moral character. They may also conduct a background check to determine whether you've had issues with crime, drugs or alcohol. Once the investigative committee has made their decision, you'll receive a call and an official invitation to join the fraternity. You'll receive further instructions about meetings.

Summary:
To be one, ask one. Interview with the Freemasons. Wait to hear their decision. Accept an invitation to join.