As you peruse the many item listings on eBay, looking for just the item you need or want, it often gets confusing to keep track of the listings that you view. When you find items you like, but you are not ready to bid or buy yet, eBay allows users to "watch" items. When you watch an item, you can keep track of bidding activity before you decide whether you will bid or purchase.
Instructions:
1) Navigate to the eBay website and log in to your account with your username and password information.
2) Search through item listings for items you desire. When you find a listing you like, click the link to view the listing.
3) Watch the item by clicking "Watch This Item" in the right corner of the listing. The listing will now appear in a list of items you are watching. Users can watch as many as 200 different listings at one time.
4) Click "My eBay" at the top right corner of the webpage. Under the "Buy" tab in the left sidebar, click "Watch" to view your list of watched items. Click any item listing to view the listing again or place a checkmark to the left of the item listing and then click "Delete" to delete the item from your watched list.
Tips and Warnings:
Create a shortcut for watching items. As you search for items and bring up search results, click the "Customized View" link beneath the search results heading. Select the "Item Information" link on the right of the next window and then place a checkmark to the left of "Watch This Item Link" from the options that appear. Click "Apply Changes" to close the window.
Source - eHow