If you see an item that you like, and want to save it to quickly get back to later - simply click on the heart icon on the top right corner of the item's image. This can be done from the item page. The heart will now be red as a confirmation. Any items that you have already bid on will automatically be in your "Following" list.
To view all of the items that you have been following or bidding on so far, simply visit your "Following" list. You can place bids from this page, as well as unfollow any items that you may no longer be interested in watching. You can unfollow items by clicking the "UNFOLLOW" link on the right hand side under "Place Bid".