Interestingly, you can learn many of these skills from the actions of your pet. Of course, you still have to learn the grammar rules; but, your pet can help you understand the approach you need to take to becoming an expert grammarian.
It takes a lot of research to uncover all the grammar rules. The details are sometimes buried in grammar textbooks.
Observing pet fashion will tell you a lot about learning grammar. Instead of just putting a sweater on your dog, the really sassy pet has a cocky hat or scarf or two pairs of brightly patterned boots. They have their own identity, just as you will have your own grammar identity once you have full use of the parts of speech.
The best way to learn about the exceptions to the rules is to look at the various ways to say something and then pick the one that solves your immediate grammar problem.
Take a clue from your dog who loves to have a daily run in the dog park. If you love a certain part of grammar, use it often. Make it your own.