Not sure how you’re supposed to do them, but I wash them well, pour in some boiling water, screw on the lid, shake it (wrapped in a teatowel!) until the lids “pops”, leave it done up until I’m ready to fill, then unscrew, tip out water and fill. Never had any mould problems, so I guess it must work!
It very much depends on what you’re preserving. Less acidic items need to be handled very careful as there is a low but real risk of botulism (eeeeeek!). The “proper” way to sterilise is to thoroughly clean with soapy water, rinse, stand in boiling water for 10 mins then dry upside down in an oven. Fill whilst still hot.
Though Nigella is right that a dishwasher set on hot (90?) will do pretty much the same thing and I would be fine about bottling jam in jars treated that way.
Same as Sarie too. That’s what my nan used to do, and then my mother, and then confirmed by a very old preserves book I have and Delia too, the original domestic goddess (I think I’m a fair bit older than most of you here lol).
I always used to do them in the dishwasher but as I don’t have one anymore I shall be following Angie’s advice to the letter. What I would say is that after using the dishwasher method I had occasional mould problems, whereas my mum who I’m not sure totally understands what a dishwasher is and basically does what Angie suggests, has never had any problems at all. But then, knowing my mum, she may have said a spell on them also.