Magento enables you to put products on sale. The sale price, or special price, is displayed with the normal price:
1. Log in to your site's backend or Admin Panel.
2. Select Catalog | Manage Products. The Manage Products page displays. You will see a list of the products in your store.
3. For the product for which you want special pricing, select the Edit link. The Product Information page displays. The General tab will be selected for you.
4. Select the Prices tab.
5. In the Special Price field, enter the special (or sale) price.
6. If you want the special price to be in effect during a specific date range, then enter the dates in the From and To fields. If you want the special price to be in effect until you remove it, then just leave the date fields blank.
7. Save and preview the product.