See I am THE most disorganised, forgetful and untidy person you could ever meet. Aside from my dad. Unfortunately I'm also naturally lazy and would rather slob out in bed watching nonsense on Youtube than have to motivate myself to get things done. BUT this year I have! I got into watching clips of Youtubers Marie Kondoing their homes last year, and I've gradually gradually been working on mine. I've decluttered so much and found a place for everything. Not that I can be relied upon to put my keys on the key hook, or that letter from the bank in my 'banking' box file, but as I don't have other crap lying around it's much harder to mislay stuff because it doesn't get buried in a heap of unrelated gubbins.
So what I'm saying in a very roundabout way is, GET RID OF EVERYTHING YOU CAN!!! It helps soooo much. Make a list now of priorities, and promise to reward yourself (or a treat for the kids might be more motivating to you?) when it's done. Don't overwhelm yourself by biting off more than you can chew, but chip away at it. Do you work full time? Even if you do I reckon you can do these things in a week, with the goal of a treat next Sunday if you manage it:
Monday: Buy (nice looking and easily identifiable) storage boxes for Important Things - passports, bank letters, birth certificates, school reports, all that stuff. Laura Ashley do nice ones, or WH Smith. Buy a large plastic art folder for each child. When they're out of the house/asleep go through all their artistic creations. Scribble and junk can be quietly 'suppressed', the nicer stuff photographed and suppressed, the special pieces preserved in the folders.
Tuesday: Tip run for stuff already set aside to go. Have a quick check in each room just before you leave and grab anything else obvious that can be chucked too. Be sure to take any of the kid's toys you know to be broken. Make sure you take the 'suppressed' artwork from yesterday.
Wednesday: Marie Kondo your wardrobe and chest of drawers. Does it Spark Joy? If the answer's 'not really' it goes in one of 2 binbags - 'Donate to charity' or 'Recycle'.
Thursday: Ditto, for the children's clothes, discard ANYTHING they're outgrown, or you know in your heart of hearts will never wear.
Friday: Go through the cups and glasses in the kitchen cupboards. This is often a spot that gets out of control because they're so often given as gifts and people don't like to chuck them. Honestly though, it gets ridiculous sometimes. I'm currently working with a family who have 40 different children's drinking vessels in their tiny kitchen. 40!! They have 3 children. Box up any that you know nobody will even remember this time next week and set them aside for Saturday when...
Saturday: You help the children sort through their toys, with the promise of a treat tomorrow if you're happy with their attitude to the task, and they offer up a decent amount. Depending on how old they are remind them that Christmas is coming and that Santa will need to see some space in their toyboxes/toy cupboard or he'll think they won't need anything more. In the afternoon, take the toys, the clothes and the glasses/mugs to the charity shop, and the other clothes to the recycling bank along with any cardboard boxes you've freed up.
Sunday: Take them to the zoo/other random treat for their wonderful decluttering. Feel good about yourself.
The idea being that that's very achievable in a week. On Monday 14th it still might not exactly feel like you're a minimalist, you might still feel like there's clutter everywhere and you're still mislaying things, but you WILL have made a difference. You should feel that bit more confident and buoyed ready to do it again! Keep at it, week by week. Don't say to yourself 'I must have everything decluttered and organised and pristine by such-a-time'. That's not realistic and you'll just feel hopeless and deflated and give up before you start. Set yourself smaller tasks you know you can easily achieve. I do what I cheesily call an '8 is great!' every day. I look around the room/house for 8 things that can be thrown away, put back where they belong or fund a new long-term location for. When I've done 8 things the room or house feels that tiny bit better to be living in. If I feel I can manage another 8 I go for it! If not, that's fine too, and I allow myself to chill out with a clear conscience. It's just a motivating way to chip-chip-chip away at it all so I feel in control again.