How do I install new speakers?

Have a 2008 Chevy Aveo Sedan LS. I have purchased Kenwood speakers for back deck and door. There are tweeters up front as well, but did not buy replacements for them. How do I remove the cover and speakers on the back deck? Also, how do I remove to install for front doors? Thanks!

Try a good mechanic, for doing yourself there is a great risk of having some other problem.