Because I have a good self image and steadily improving self esteem, it does not diminish me to tell somebody they are doing something or have achieved something that I found impressive.
That is called "a compliment."
Today alone I have had two odd people interpret my compliments as insults. Now having a Master's degree in Communication, I know when I mess up my attempt to convey something and in both cases it was pretty darn evident what I was saying was a compliment.
Let's make things real easy.
When somebody says, "You are a very good artist" or "You have written something that moves me" or "You have done something very impressive" the proper response is simply "Thank you."
That's it. It's a simple "Thank you."
Now if you have a psychological hangup where receiving a compliment is the equivalent of being flayed to death via paper cuts and you would rather be eaten alive by Giant Sumatran Rats than hear "Good job!," at least take personal responsibility for your mental maladjustment and don't insult the person who compliments you.
Even though you may feel it will be the equivalent of having your sinuses irrigated with hydrochloric acid, you might want to grit your teeth anyway and simply say "Thank you."
It's what all the cool, sane people are doing nowadays.