Magento offers simple category and product ordering although this may not be obvious at first. I thought I might share this simple information.

Category ordering

To change the order of categories, from within the Admin, go to Catalog -> Manage Categories. Simply drag and drop the category or subcategory to the location you need it.

Product ordering

As products can belong to multiple categories, to order them you will need to go and order them within the categories. From within Admin go to Catalog -> Manage Categories. Select the category to order it’s products. Now go to the category’s ‘Category Products’ tab. Here you will see all products that belong to the category. The last column in the table is the Position and sets the ordering of products within the category.

So there it is! Nothing to it!