At this time there are no more rules because those are set by you. But if there are trends and wearing several rings on the hands is one of them.
How to combine them in order to get chic look.
For an elegant hand:
Choose several rings in the same tone, but with different textures and place them on different fingers, including the thumb. Then you can stack some more in a few fingers.
For a modern hand:
Look for rings that are of different sizes, colors, and shapes. Place the largest ones on the index and ring fingers and complement with smaller ones on the other fingers.
For a thematic hand
Choose what you want to express. If you want to join our message that LOVE COMES IN ALL COLORS, wear rings from the rainbow collection. Large, small, and some together on one finger.
For an engaged hand
Do you have an engagement and wedding ring? Fantastic, take advantage of his style and complement the look by using other infinity bands and solitaires for the other fingers. Even to wear several rings in each one.