Tipping is a very personal thing.  Everyone is different.  Some people tip large, some small, and of course some not at all!  Many visitors generally tip around 10% or sometimes 20% of the bill.

Tips are very much welcomed.  

When you return to an establishment where you have previously tipped, you may be remembered and greeted with a smile and swifter service.  

In Slovenia a tip is not an obligation, but is appropriate for good service.