Playthings prevent boredom and misbehavior. They need not be expensive or store-bought. Make clear rules. The fewer rules you make the better. They should be reasonable.
Consistent enforcement provides security and tells the child rules are important.
There may be special times when rules can be relaxed, but not forgotten. Rules will need to change as the child grows in ability and responsibility. Set a good example. Children imitate those around them. They learn what they live.