If you have just purchased a Canon 500D DSLR (Canon 500D Rebel T1i) and are confused by the sheer number of buttons and options available, have no fear. I went through the exact same feeling when I got my Nikon D5000 and so, I can relate to how you feel. However, with a little knowledge of what all the buttons do, and which options to use for what purpose, you will be ready to start shooting beautiful photos!
This short Canon DSLR tutorial on using the Canon 500D Rebel T1i will help you get started.
Attaching / Removing the Lens
The first step is fitting the lens onto the camera. As explained in the manual, all you need to do while fitting the lens is to align the index dot on the lens with that on the camera body and rotate it counter-clockwise till you hear an audible click (the lens has locked into place). To remove the lens, press the lens-release button and rotate the lens clock-wise till it gets detached from the camera body. Practice this a couple of times till you get the hang of it, so that you're ready to do it in a jiffy when needed.
The Lens Focus Mode can be set to AF (Auto-Focus) or MF (Manual Focus).
Beginners should choose AF and the Image Stabilizer should be On.
Zooming is achieved by turning the zoom ring on the lens. Always remember to zoom in or out prior to focussing, otherwise you may end up with a blurred picture.