Selecting images - do a google search, I'm very picky about which images I choose. I suggest using google and searching for 'green bottle' or 'red bottle'. Remember, we want to select a relatively plain bottle for this tutorial. I'm going to be dealing with lighting effects.
copy image from google and then go file:new>okay>edit:paste
Here are some images you can use:
Don't forget the Background images (use pretty scenery or models on google):