Since you can contact matches through an online dating service's internal communication system, there's no need to reveal your address or phone number.
When you do communicate with other members, keep in mind the possibility that any stranger could be a liar or a scammer. Don't enter into any financial arrangements with anyone you've just met.
You might also tailor your messages and profile in order to make them more appealing.
For example, overly aggressive messages or messages with poor spelling and grammar are less likely to receive a response. It's important to create a profile that represents you in a flattering light.
Don't feel obligated to meet every match in person.