Step #1
First commence the tutorial by making three circles & a tiny line as shown.
Step #2
Draw outline for tail & draw a straight line as shown.
Step #3
Make head & eye.
Step #4
Draw outline for body.
Step #5
Make fins & tail.
Step #6
Make gill shape as shown & fins.
Step #7
Draw retinas & lines over the tail and fins as shown.
Step #8
Draw small circular shapes all over the body as shown.
Step #9
Finally, make necessary improvements to finish.