"It is important that studying chess tactics should precede the detailed study of strategy. The amateur needs only the elementary knowledge of strategical principles, while paying extra attention to calculating chess combinations. The following scenario is all too common: one of the opponents, after studying numerous chess books, builds his position on the basis of the most scientific principles of the modern chess school… only to succumb to a simple two-move trap. The longstanding Soviet Women Champion [Olga] Rubtsova scored many points on tactical traps against the opponents who had extensive knowledge of the positional struggle, openings and endgames, but were helpless in calculating combinations. Even in the style of certain masters there is a lack of balance between tactics and strategy, which stems from the time when they started to climb the first steps on the ladder of chess successes. Such masters instinctively avoid complications, and when they are forced into them after all, the class of their play drops dramatically. Steinitz, the creator of positional school, in his younger days recognized only tactical struggle. The chess development of Lasker, Capablanca, Alekhine, Nimzowitsch, Réti and other first-class masters followed a similar path." (How To Improve Your Chess Qualification, published in the bulletin of Kuibyshev 1942 tournament, no. 4, p. 7)
Tip: Another way to improve your positional play is to play "Solitaire Chess" using the games of strong positional players (Smyslov, Petrosian, Flohr, Karpov, Kholmov, and Hübner). U.S. Senior Champion Grandmaster Fishbein trains this way: