I think it is very hard to keep a house tidy unless you have set it up to work from the start.
Basically I think you need a place for everything, and only then can you put things away - but the place itself has to be ergonomic, as it were, (not sure if that's the right word) what I mean is it has to be intuitive and easy to maintain.
So, a shelf or hook by the door for your keys (easy)
keep shoes and boots where you put them on or take them off
keep papers near your desk
important stuff in a particular place
I've moved from a flat to another flat and this one works very well and is much tidier, simply because the layout works better for us - so we have proper sized bedrooms for the children, not one huge room for me and a tiny room for them - all toys instantly belong upstairs. Sorted.
Clothes belong on the upper landing in a giant chest of drawers - this means all their clothes stay there, even if they leave them on the floor, and I can put them away or in the washing without having to search among their toys, or even go into their rooms.
The only problem we really have is a small hallway and landings, which means we have nowhere to keep shoes or pushchairs and that really annoys me because our last hallway was vast. 
You can't have it all!
but another bonus here is that we have put the washing machine in the bathroom, which is pretty big, and that means the aundry cycle is very compact - clothes get taken off before a bath or shower, bunged straight into the machine and out again to hang up on the airer.
I also have a large number of plastic lidded boxes in which I try to sort various items so they are all together - and small stationery drawers - for pens, pencils, rubbers, rulers - a box for coloured papers for the children to use - it's all got its own little department. I have discovered I have about 300 pencils and maybe 20 pencil sharpeners
I will never need to buy anything ever again just because the existing one is lost.
I've gone from total chaos to - well, Bohemian perhaps
as we don't make much effort, so it's still a bit of a tip - but at least I can find my pants. And things do HAVE a place so when I want to tidy up, I can, and it looks nice.
It's setting it up that makes the difference. Otherwise you will forever have random boxes and bags of STUFF that has no home.
It's taken me almost a year to get this far but it is so much calmer to live in.