I have three with one on the way. It’s a constant struggle to keep the place livable. Before I had children I was not a neat person and kept things livable by not doing things that made mess and staying out as much as possible. Can’t do that with kids, so what’s the trick?
Short answer: we don’t.
Long answer: clean up your shit, or your friend will not come over / your allowance this month will be going to my pocket. Do you want to eat? Help clean out the kitchen/dining table. I did place their plate of dinner food over the one from lunch that they didn’t put away. They didn’t like that.
It also varies a lot from kid to kid in my family. One of them is a crafter and a hoarder. Carton boxes, glue, scissors, pieces of paper, colored beads all over the room. Once in a while I tell her to clean up, and anything she doesn’t, I will scoop up and throw away. Her sister has a spotless room… nothing to complain about. Their brother, every couple of days he will have a new videogame ask, or a new Minecraft server I should set up for him and his friends… Again, I will do so, when I see all the cans, plates of food and clothes on the floor put away.
I second this. We have a very similar situation. I will note that I’ve begun using a “carrot” approach as well as the stick. I now keep relatively cheap and fun crafts and electronics around. Cleaning a room and helping out will earn them a fun craft and that seems to work REALLY well lately. If you know how to solder you can buy a bunch of cheap but fun kits that you can do with them and reward them with as prizes. Today’s (if they are compliant and helpful) is an FM radio. I do bigger ones if they do more, and I expect more on a weekend.