Adding Product Images

You can edit product images in your magento admin panel

Navigate to 

CATALOG > MANAGE PRODUCTS

Here you can search to locate the product you want to add images too

When you have located and selected the product go to the "Images" tab down the left side

To add new images first select the "Browse Files.." Button

Select the files you want from the popup and click okay

Then to add them to the site click "Upload Files"

These will then appear in the table with a preview

Make sure you main image has the radio buttons ticked for "Base Image", "Small Image" and "Thumbnail"