The canvas or surface you paint on is essential to a good painting. I've tried numerous tricks and hacks to improve my art to become a better artist and nothing has helped more than this simple trick.
Applying additional gesso can often times be the solution to your problems if you struggle with blending paint. Store bought canvas can be very rough and this technique for applying the gesso will help you tremendously! The way you apply the gesso has everything to do with it and I've found that by using a straight edge instead of a brush, I can achieve better results.