I have items that are not from seasonal sets nor decorations. They are stand alone. How do I group..

You can be creative, or you can store them away.

Last year I got skeleton cats that I had no clue what to do w them so I put them near the graveyard w the kids in costumes. ..this month all of the prizes have been from an old day of the dead set which is where the cats are from and I've practically put the whole scene together now!! So place your stand alone items wherever they seem to make sense and look out for prizes that they might belong with!!!