An effective way to memorize and understand primary chords for each major scale is to write them out for yourself. You might even consider writing out EVERY chord for all the major scales. This exercise will help you internalize every chord associated with each major scale.

Additionally, you’ll also familiarize yourself with the primary chords of each scale. For a piano player this exercise is as important as memorizing a times table is to a 3rd grader. In order to be a proficient piano player, you need to know your primary chords inside out.

The primary chords are the 1, 4, 5 chords. For example, the primary chords of the C major scale are C major chord, F major chord, and G major chord. 

Another fun way to learn about chords is to draw a chord wheel. The chord wheel can also expand to include an additional circle of fifths such as the following: