Chess maxims are abound, especially from acclaimed players like Siegbert Tarrasch who was the authority in explaining the importance of chess rules in his time. Today we have a summarised guide of these bits of advice in the form of the 2 books below:
"The most important novelties are hidden in the games of the old masters"
That's why the study of the games of Alekhine, Nimzowitsch and Capablanca will gain you valuable insights on some of the plans they've used and are likely to spin off in positions of current theory.
I highly recommend this be holiday reading for those having some time on their hands before they take part in another chess tournament. General maxims like ' the threat is stronger than its execution' or ' do not create more weaknesses when you are in a bad position"