Maybe you're not a Church-goer. Maybe you just never find the time, or you don't think it's too important. Maybe you believe in God, but not in religion. There are many reasons why you might be someone who's asleep on Sundays while others are at mass. But I want you to know something, and I give this to you not out of judgement, but out of love for you.
God believes in you. God believes in the religion he established. God is all over you, day and night, with total interest in you, and in everything you do in your day. God sees you, and He knows you. He knows everything that's good, and bad about you. And one of the things He knows about you that you may be in denial of is that you're a sinner. We all are. And I'm giving you this wisdom as one sinner to another sinner.
Sin is terrible. Whether we want to believe it or not, God sees it as it is, and knows it to be true. Sin is terrible. So as sinners we can't afford to be indifferent to God, the Father of mercy. We can't afford to be indifferent to Jesus Christ, the just Judge. We need God's mercy, in abundance. Fortunately for us God is eager to give us his mercy. But we have to ask for it. Ask him for it every day, because you need it.
"...from God's perspective, this little act is substantial"
You can start off simpler than you think, no matter how long it's been since you've been to Church or prayed. Here's something you can do that's so simple it can almost seem insignificant. But from God's perspective, this little act is substantial.
Go to a Church. Light a candle. Now, while looking at a crucifix, or at the Tabernacle, bless yourself, and say "My Jesus, have mercy on me, a sinner".
Stay a while, or leave right after you say that prayer. That's up to you (and the holy Spirit). But make this little act of reparation at every opportunity that you get (when passing a Church during your day, for example), and you'll be on your way to getting right with God. Ask God for mercy. Ask him, and ask him, and ask him. Ten times a day. A hundred. Ask him. We need his mercy
If you've ever said to yourself "One of these days I really should get back to church", then stand by, and be ready. Because before long, after saying that brief littler prayer for a while, you'll be back in church going to mass, and you'll even be back in the confessional. Not because you'll be compelled by guilt, but because you'll feel drawn to it by grace. You'll thirst for it, as Christ thirsted for you from the cross, and still thirsts for you right now...literally at this very moment.
A couple of parting words. The best way to make that act of reparation is exactly as I wrote it. At a Church, after lighting a candle, and looking at/meditating on the crucifix or tabernacle. Modify it if you need to. Any plea for God's mercy is heard in Heaven. But making a little sacrifice of some kind (paying a buck to light a candle, for example), and being in the presence of the Holy (being at church) does make the prayer a little more effective.
Okay. Now go find Jesus, and make friends. I love you.
Ave Maria, virgo fidelis!