I need to raise my photoshop skills

Already for a year I am trying to study CS Photoshop program . Unlucky i cant go through 8 hours of self-education. I need this skills to raise my competence in business and projects I am doing, for example i need to sell a painting through internet, so the photo cam cant deeply transmit the colors and original idea of this painting, so knowledge of Photoshop will give me skills i need to make it( i mean in the end sell the painting). Also i got a good friend who can give me some freelancing job and teach me a lot more about this program, that is just what i need right now!