Photoshop Frustrations

I have just spent the last four hours sitting in our sub-zero temperature classroom shivering and attempting to figure out how to use the Photoshop program. Part of the problem was remembering all of the things we did in class last week, THAT was not easy. Luckily, one of our classmates was here with me and between the two of us we were able to sort of figure things out. In my reproduction of the Wassily Kandinsky drawing I became very frustrated in trying to make circles transparent and outline them. I also did not know how to combine colors into each half of the circle. If I see the word rastersize one more time I'm going to scream !! The other issue was trying to make the entire background black without it either blending in with the shapes on the screen or my brush strokes ruining the shape I had drawn. When I started doing my own drawing, it was easier to play around with the shapes and positioning them to where I wanted them to be. This is going to take a lot of time to practice and tinker with.