Since the given image has a theme of underwater. The best thing to add is some fishes and other sea creatures. By just looking at it I feel like I am watching the movie, Finding Nemo, but in here they are safe because I did not include any sharks.
Let's Make a Collage - A Contest for All Creatives in the Hive - Round 60 - ✨154 HIVE in this Round's Prize Pool!
The stickers were from the Canva app provided for free.