Step #1
Start the drawing by sketching two circles & a tiny line as shown.
Step #2
Draw outline for tail. Also draw a straight line in the middle of the body.
Step #3
Make head, mouth & eye.
Step #4
Draw outline for body.
Step #5
Draw gill shape as shown.
Step #6
Make upper fins & tail.
Step #7
Draw bottom fins & gill shape as shown.
Step #8
Finally, make necessary improvements to finish.