Need Help Configuring MAGENTO Store

I have an online shoe store that was built using Magento Community ecommerce software. I need assistance configuring categories and creating size/color options that work in drop down menus. For example, a couple of the shoes are the same style just different colors and sizes. Magento is already installed and the store is online I just need to know how to make adjustments. I also need a paypal account integrated into the payment feature. The website is [login to view URL] I need help as soon as possible. Serious inquiries only please.