The most heartbreaking option is to read a bunch of the bereavement threads. There are so many dangers! That said, for me my Jefferson Wants To Fly and so I have progressively declared various room "Bird Safe ENOUGH." After the 2nd room was achieved, I stood back and asked myself what exactly was my criteria?
Well I'm a bit of a clutterbug. For me, the big criteria -- are there Places in this room where a bird could get to, or get itself into trouble, that I couldn't safely retrieve him or her? Or, that I couldn't reach her without further endangering a birdie?
And with this thought, it turns out, my kitchen can probably Never be bird-safe. Well, kitchens aren't anyways -- but even if everything put away & etc -- I have an open alcove with storage shelf with pots & pans racks, they rest against each other etc. There are certain things which cannot be moved without causing other things to move also.
So I make sure the kitchen is closed-off when the budgies' cage is open. In the past Jefferson has flown in there, & out again without landing, but thankfully Calliope has Not. Jefferson never goes anywhere - or does anything - that he didn't intend to. But Calliope occasionally lands imperfectly, or chooses to land in odd places or behind things
I've gotten rid of all glassware. From years past I know that broken glass bits hang around a long time even when you thought you'd gotten them all. And Sunny occasionally does unexpected jump-downs. So, NO glassware except the UNbreakable kind. And I like Large mugs, so I've made sure all my mugs have openings wider than their bases. Just In Case somebudgie were to decide to go for a swim.
(I may have to amp-up my definition of "Bird-Safe ENOUGH" once Sunny finally gets all her feathers. She definitely has much more interest in technology than the budgies. )
I also think a bird-proofing sticky would be a good idea.