My 4yo DS puts his dirty clothes in the laundry basket and puts his clean clothes in the drawers and he cleans up his toys every evening before bed. Usually I help him clean up his toys but not always. He's perfectly capable of doing it on his own. We've been doing it since he was physically able to go pick up that block and put it in the basket or whatever, probably just a little over a year old. I've always tried to be very matter of fact about, I don't call it a chore or a job, I don't reward him (other than saying he made his room look very nice) I've always tried to make it just something we do, like clean up toys, get jammies on, brush teeth.
I think I messed up with my older kids when they were little because I didn't think they were able to do so much and it was just easier to do it myself and then as they got a little older I made it into to big of a deal and met with much resistance.
I've done things differently with my 4yo and I like the results
He may not be the most efficient helper around the house but he's by far the most enthusiastic. He'll often ask to help dust furniture, do laundry, ect, and I'm happy to let him.