-- Look up and learn the "rule of thirds." would help a lot with picture composition
-- If it's not turned on already, enable the 3x3 grid on your display (for rule of thirds)
-- Try playing around with different angles when you shoot to see what works and what not. Like how would that bottle look if you were looking "up" at it? or the stack of games, how would it look if you caught it from one end as the games cascaded away from the camera?
-- If shooting manual is a bit overbearing for you right now, try focusing on just one particular setting to adjust. Like if you want to shoot a fast moving object, use the Tv setting (you're on a canon, right?) and just worry about adjusting the shutter speed to your liking. Or if you want to shoot a pic with some sweet background blur, just use the Av setting and change the aperture to your liking). might be a bit easier to learn how these settings play off each other by focusing on one at a time.