Step 1: Draw a small circle with a dot in it for the eye.
Step 2: Use curved lines to create the head.
Step 3: Make a bumpy line with two large bumps for the nostrils.
Step 4: Create a ovular shape for the mouth.
Step 5: Draw downward curved lines to create the barbels.
Step 6: Use curved lines to create the fins and then straight-ish lines to create details in the fins.
How to Draw a Koi Fish Face – Step-by-Step Tutorial