Of all the grammar books I’ve read, the best one I’ve come across is Mignon Fogarty’s “Quick and Dirty Tips for Better Writing.” I’d recommend either that one or the smaller “Punctuation 911” depending on where you’re weak points are.
What I love about Fogarty’s work is that she acknowledges the purpose of grammar. The purpose is not to play the role of the Grammar Police and assert yourself as intellectually superior to another person. Rather it is to communicate clearly and effectively.
Teaching grammar to young people is a manner of socializing people into a very strict usage of the language. It’s a way to work against the development of local dialects that would eventually evolve into other languages with their own rules. And as such the hope is for a wider expanse of people to be able to communicate effectively with each other.
Even with institutions like the Modern Language Association though, she acknowledges that grammarians aren’t always in agreement. Style guides can contradict each other. She explains these facts concisely and clearly, gives great examples and allows the writer to choose among their legitimate options.
My recommendation is to go through the book, highlight the points that surprise you and then create a cheat guide for yourself on areas you might need to reference later. A one page cheat guide aimed at your own areas of weakness can be invaluable. Every time you reference it and correct your own mistake in your work, you work toward learning the rule more effectively.