Step #1
Start the work by drawing two circles & a tiny curve line.
Step #2
Draw outline for tail & fins. Also draw a line in the middle of the body.
Step #3
Make head, gill & mouth.
Step #4
Draw outline for body and draw an eye.
Step #5
Make five fins.
Step #6
Make tail as shown.
Step #7
Make lines over the fins and tail as shown. Also draw a retina.
Step #8
Finally, make necessary improvements to finish.