Hi Damian.
What a great question you have asked!
Let me start by saying that sharing the good news of Jesus with your family is often the hardest thing to do. Let me give you three things to do.
First, and perhaps most obviously, PRAY.
Pray everyday, pray specifically and pray that God would do his work of bringing them to repentance and faith. It is God’s work and he loves to hear and answer our prayers. Pray too that there might be other people that they know who are Christians who will tell them about Jesus too.
Second, LIVE A GODLY LIFE.
1 Peter 2:12 says, Live such good lives among the pagans that, though they accuse you of doing wrong, they may see your good deeds and glorify God on the day he visits us. This verse sounds like it may apply to you epecially if you fear that they know your faults. Work hard at your godliness, service of them and kindnes towards them. They will see this change in you and see the work of Jesus in you and hopefully see that that change comes through Jesus.
Third, TAKE OPPORTUNITIES.
I say this as opposed to making opportunities. Sometimes we can have had so many opportunities that we have made to tell those closest to us about Jesus, that we are best to give it a rest for a time and spend more time praying. Then when the time is right, and they raise something, you can make a comment or ask a question that may lead them to think afresh about Jesus and his love for them. What I mean, is don’t keep forcing conversations, but perhaps for a time, wait for them to come up, praying of course that they would. Sometimes a “softly softly” approach is effective - looking for ways to mention things about God rather than seek a full blown discussion.
Above all be assured that God loves your family as much as (if not more) than you do and he knows what he is doing.
I hope this is helpful and I will pray for you now.
Nigel