Probably goes without saying that there are as many ways to learn Japanese as there are students. The only really hard-and-fast rule is that whatever you're doing, you need to do a lot more of it than you think.

That said, I've found that the kanji separately really helped my Japanese studying. If nothing else, it's kept me from falling too far behind the Chinese and Taiwanese students in class...

The book I used for the kanji is The Kodansha Kanji Learner's Course by Andrew Scott Conning. Can't recommend it enough.

https://www.amazon.com/Kodansha-Kanji-Learners-Course-Step/d...