You can type the item number in the search box and it will bring it up.
Then click and drag the sides of the window so it takes up half of your screen and you can see your auction item and the icon you need to click on to bid. Click on that box to Restore Down the window size. Keep reloading or refreshing the page to keep a better watch on the time. Lets say you're willing to pay $10 for it. If it's still in a nice price range, then sit back and wait. Record the item number and auction end time. Note when it finishes and remember this for later.
Watch the auction you're interested in.