Anyone should be able to change their attitudes and make adjustments to better orient themselves from a worldly way of thinking to that of a Christian. It’s not uncommon to have a myriad of corruptions that sully our character, and the goal would be to have no corruptions in the end. The sooner you can self-analyze and correct course, the better.
We Americans have a tendency to be self-centered. Look at being more open and more giving. When you start going to church you should start tithing, which means to donate 10% of your income to a church or a truly good charity. (Samaritan’s Purse comes to mind.) Try to donate, but don’t if you truly can’t afford it. That’s a start. It’s a change to how you used to be as someone who wasn’t a churchgoer. If you have school-age children, they need church for the sake of their souls, too. They need to learn to always be honest and never ever sin, and not just that. They need to think and remember every time they’ve ever sinned, and ask God to forgive them for each instance while they’re young.
Work on avoiding disrespect. People sometimes have disrespectful thoughts at times for humor, or to build one’s self up at the expense of lowering someone else. Check your conscience, should that happen. Comedy can be vulgar in this day and age, and it can really traffic in negativity, so adjust your judgment. A sense of humor is a good thing, however it should not involve malice, wickedness, rudeness, violence, and the negative emotions.
Humble yourself. Be patient and tolerant of others. Be easy going toward people. Be forgiving.
Stop holding grudges. An exercise you should try is completely forgiving everybody who has ever wronged you in your whole life. That may be hard or bordering on impossible, but if you can work it out, that can be a huge burden to free yourself of. Sometimes this can lead to miraculous healing.