Many people find grammar uninteresting because of the intricacies involved in the rules themselves. You have to remember certain collocations, consider some exceptions, and take note of overlapping uses. While it may not be as exciting to learn as other language skills, it pays to revisit some rules or learn new ones from time to time if you really want to achieve some progress in the language.
You can learn grammar indirectly by reading different materials of interest. Constant exposure to authentic materials such as news articles will familiarize you with certain structures. However, if you’re curious as to the exact uses of certain grammatical items, for example, conjunctions, it always helps to consult a grammar book in your spare time or have a quick look at some reliable websites that can give you a thorough or quick explanation.
To put your knowledge to test and reinforce it, instead of doing the usual exercises, you might find it more enjoyable by engaging yourself in grammar games. It will alleviate the boredom that is normally associated with grammar exercises and will help you keep your interest.
Finally, to put that knowledge to good use, try writing sentences that are true for you using the grammatical item that you have just learnt. Don’t just write for the sake of writing examples, but make it more realistic by actually drawing from your own experience to help make that grammatical item more meaningful to you.