My kids don’t put their things away. They always ask me where everything is.
Have your kids decide on homes for their things. After they have decided, have them give the homes labels. Here, a 5 year old has labeled her jewelry and stickers drawers. (So nice, eh?!)
Help create the habit of putting things in their homes. At the end of each day, set a timer and see how long it takes to get everything in its home.