1) You can click on the heart to start/stop following a lot on all auction pages and lot detail pages. 
2) When you place a bid on a lot, we automatically favourite the lot for you.

We will notify you when your favourite lots are about to close. This way you'll never miss your chance to place the winning bid!

Your favourite lots can be managed from this page:
https://www.catawiki.com/en/interests/object