For many years I have been involved with Cursillo, which is an adult faith formation program. In it, there are a number of talks, on a number of topics, including evangelization. In that talk, those who are participating in the weekend are encouraged to consider reaching out to family or friends who are unchurched, or who have fallen away from the faith, to invite them to come to church and to come to Christ. This is very intimidating to most Catholics, so the talk is intended to help prepare participants to feel more comfortable.
One of the points in the talk is to make sure that “we talk with God about our friend, before we talk to our friend about God.” Do not go rushing in to encourage someone to come to the Church, or to return to the Church. It is possible to do more damage than good when doing that.
Think about the person to whom you wish to reach out. What do you know about them and their history with God or with religion? Do they seem like they would be open, or would they be resistant and resentful? Are you the one to reach out to them on this?
Pray about this, and ask God to show you how and when to speak to them. Don’t nag or talk down to them. No one has ever been converted by a wagging finger. Pray for them. Ask the Holy Spirit and the Mother of God (they are the ones I go to in these situations), and ask them to speak to the heart of the individual, as well as to your heart. If, perhaps, you are not the one to reach out to them, ask them to ask God to send the right person to them.
Prayer is the most powerful and effective evangelization tool that we have. Do not neglect it.