Read Nimzowitsch's "My System": https://en.wikipedia.org/wiki/My_System

Everything you need is in that book. It's not too long, and very readable. It has a very common-sense approach. Look for the 21st century edition at used book stores or your chess club: http://www.amazon.com/My-System-21st-Century-Edition/dp/1880...

chesstempo.com is good for practicing tactics between games.

I'd highly recommend "My System" by Aron Nimzowitsch. A deep dive into positional play instead of specific tactics

http://www.amazon.com/My-System-21st-Century-Edition/dp/1880...