Once you start your game there should be no intro before it loads, and when you're in game, there should be no sparkles when you are building walls. Now you need to start your game to make sure your folders are set up right. This will tell you how to set up the folders you will need for downloading custom content (CC). You should now know how to unzip a file and have a program that does this (like 7zip, winzip.)
So first, if you don't know what ' extracting files' or ' unzipping' is, go here. I'm going to be lazy and link you to pages that will tell you what to do. This is for littlemotorkitty, and anyone else with a passion for The Sims :D