I don't clean up as often as I should even though (maybe because) it's so easy and fast to do. When I had tons of stuff without homes and tons of stuff that needed to leave the house, I'd clean up at least a bit every day.
Now, I can let things go for a week, and put it all away and sweep up in less than 30 minutes (while reading a book so most of the work is one-handed) of pretty casual work.
But things get pretty crumb-filled in the interim, so...
Things I'm already doing:
having dd put away one toy before getting out another (I do allow her to play with toys together, but if she just stops playing with one, I at least get her to ask me to clean it up for her)
when going from one room to another, taking stuff that belongs in the second room
when chasing dd around, putting stuff away as I come across it.
brushing off the couch after dd's snacks.
Most stuff stays put away most of the time, it just takes special effort for enough to be put away that I can sweep. And if I don't sweep, it's crumb land.