How do you know if you have a blown fuse?

I'm curious, how exactly can one ascertain whether or not they have encountered a blown fuse? What are the telltale signs or indicators that should be on the lookout for? Additionally, are there any particular steps or precautions one should take in identifying a blown fuse safely and effectively? Understanding this would certainly come in handy for anyone looking to tackle electrical issues with a level of competence and assurance.