What is the key signature?

   In musical notation, a key signature is a set of sharp, flat, and rarely, natural symbols placed together on the staff. Key signatures are generally written immediately after the clef at the beginning of a line of musical notation, although they can appear in other parts of a score, notably after a double barline.

Explanation:  hope it helps

i dont really know what you want to draw but what about a fish? ?

if you are asking for suggestions?