I have never completed a color chart.  I have made the little color wheel with primary, secondary, etc but that doesn't count.  This week I finished a full color chart using all of the colors in my pan, 22.  It took days but I highly recommend you do it.  All of the color combinations, from just two colors each, blew my mind.  All of the greens and blues alone is enough reason to do this.  I have taken online classes where the teachers discouraged buying green and now I can really see why.  The rainbow of warm and cool greens you can get from mixing are endless and rich.

Such a great exercise.  It's a little like learning to type.  First you are pecking at the keys because you aren't sure where they are but eventually you have the keyboard memorized (in this case watercolors) and it is just one more thing to do to get you more comfortable.  I used this tutorial for mine.

Do it too and come back and share here.  You can do it, I can't wait to see!  :)