At some point you may wish to meet in person the friend you have made. Remember the rule; you only have to meet someone if you really want to. If you feel uncomfortable about meeting, then don't agree to meet. Even if you have agreed, you can change your mind whenever you like. Perhaps you need to chat for longer; perhaps it would be better to use the phone first. Do not give out your home number, address, or personal details unless you are sure about the person you wish to meet.
If you do decide it's time to take your friendship a step further then here are some things to think about. It may save you a great deal of time and effort: