Never give out your phone number or address until you’ve met them in person and feel comfortable with that.
Always meet in a public place and, when you leave to go home, make sure that your’e not followed.
Find out where they work, what church they go to, what school they went to and when they graduated. you never know, you might know someone that works with them or goes to the same church or went to school with them. That happened to a friend of mine, she found out he used to work a certain place that one of her friends used to work and, through the friend, she found out that he’s OK. She also found out that I know him so she asked me. They got married and celebrated their 3rd anniversary last month.