It’s unlikely that your dog’s barking is just for fun. However, it may be done to communicate that they are having fun, for instance, when you are playing with them. While you can forgive the odd “ruff” here and there, if your pup’s vocalizations get out of control when you give them attention, you need to withdraw that attention. Over time your pal will get the message that barking means the end of playtime and will replace this with better ways to express their delight.