A bit about sentimental stuff - an idea that I used from a declutter guru some time ago. As well as having boxes for keep, bin, charity shop, have one called emotional withdrawal and stuff that you are not sure about for emotional/sentimental reasons put it in there and put it out of the way for a few months or until you are ready to look at it. Or longer if you need to. Actually ,Marie Kondo suggests leaving sentimental stuff until last, but don't think she suggests boxing it up, but boxing it up while you are going through stuff to me saves time, and makes space. You might want to do different boxes if you have a lot, maybe for different people, different categories of stuff. If you blithely chuck stuff in a fit of get rid ASAP and on reflection realise a few weeks down the line that you really wish you'd kept it, then this is likely to discourage you from decluttering. Likewise, with clothing, it's all very well saying if you don't use it in 6 months you won't wear it, surely I'm not the only person who some years doesn't need the big warm snow boots, but will wear them next year if the weather is snowy. If you remove seasonal clothes to bags in the loft this is a good time to look at clothes and think is it worth putting this in the loft, as it's getting tatty, and again when bringing them down again, do you want to put that tatty old skirt in the wardrobe again. Clothes in general [ not sentimental stuff like your mum's favourite scarf or wedding dress] - if they fit would I wear them ever,, do they actually suit me, or flatter me, do I have anything to go with them, if not, is it worth getting a top or a skirt to go with them, or would a bit of an alteration or mend make them clothes I'd want to wear again and if so get them sorted, are they clothes for a specific occasion eg a funeral, a job interview that would need replacing if discarded, why hang onto them if they will never be worn. I've been known to take old clothes with me on a camping holiday where things get mucky, and instead of taking them home to put in the rag bag for the charity shop, have actually just thrown them away. Sorry, I usually bag up rags and hope that the green gurus will understand, it is saving water and washing owder not washing them
With other things such as furniture I have asked myself in the past if I had a huge house and everything would fit in, would I want to actually use it - if the answer is no, either just get rid or if you actually still need something to do the job that it does, hang onto it and start looking for things that would do the job as well or better that are smaller/more your style/whatever [and then get rid of it]
And at this time of year, taking down decorations, it's a good time to think what you want to keep, I've decided for example to get rid of a perfectly good card hanger because with things rearranged it gets knocked every time someone goes past it carrying something, don't want that next year - it would be fine for someone else with a different set up. I decided to give our old very distinctly coloured lights to my children, they were the ex's choice, and even if they weren't they need a ladder to put them up, I splashed out in the week before Christmas at the local garden centre which was selling Christmas stuff off half price. I don't mind seeing them at the children's houses. So what goes back in the loft will be things I actually want, , which includes stuff from my parents, some old ornaments etc, I just got rid of some 'meh' stuff that I had so no extra space needed and next December there will be no sorting through, or boxes still up there with things I don't want
Decluttering needs to be combined with getting organised for me, so this year it will be really great to have only the boxes and bags that have stuff I will need. I discovered that I had boxes up there which never came down, so was never sorted, which sort of acted as a bit of a clutter magnet.
Yes I have got rid of some things that I regretted, but nothing that I couldn't cheaply replace or replace for free .