There are plenty of ways depending on your level of knowledge an what you are willing to do. I would say praying the rosary daily is one of the best ways. Want a scientific explanation? Well, you know that sound waves travel through all the universe, so it wouldn’t be crazy to say they could reach God even if He received the sound waves outside the universe (because the sound waves reach the limit of the universe). And if you know with technology we can see through a microscope and telescope, then it wouldn’t be imposible for a being to have a mechanism to see our brains from far away, because thoughts are made with physical substances in the brain. They may not be the best examples, but they are reasonable even if hard.
The first christians were sometimes called philosophers by the greeks, and not just because of their moral reasoning. Pope Benedict XVI, for example, said that a rational being can not have been created by something irrational (like chance). Another of the great things in the Church are the teachings that you can apply in your life and see for yourself that are part of human nature and bring happiness. Cardinal virtues, the opposition against capital sins, are christian teachings, and a society can’t know why easily because we have limited experiences and our lives can specialize just in some things and won’t ever know about the rest.
However, Christianity didn’t expand only by promising the truth to everyone but by miracles. You could research miracles of the Church, and it wouldn’t be a bad way to learn, but that isn’t the only way God acts either. God is the Creator of all and it wouldn’t be reasonable to think He doesn’t use nature. Personally, I see too many “coincidences” in my life to say that they are fruit of chance, it is clear to me that God helps me at all times. Aren’t there scientific theories that say that everything tends to chaos? Well, one of the teachings of Jesus says that if you keep looking, you’ll find what you’re looking for. As long as you are sincere and keep looking for the truth, you’ll find it when you need it. I recommend that you get some helping hands from a community, even if it’s hard to find a good one today.