To become a good Blues player, it is important to develop the ability to improvise. A good way to do this is to use the right hand to improvise short lines with the Blues scale while playing a shuffle with the left hand. First, practice the scale itself over one chord, then use the whole 12 bar progression.
Here is a Blues scale idea played over a shuffle left hand part for a C chord.
This time, the initial triplet figure is repeated to create a longer variation.
Here is a 12 Bar Blues solo which makes use of these techniques. By this time you know enough to start improvising your own Blues solos. You could use any of the ideas presented so far as a starting point. The main thing is to experiment and have fun with the music, remembering that the more you do it, the better you get. It also helps to have some kind of a theme in your playing and to develop it through repetition and variation.