Origami Fish Base: It is a fold used as the starting point for creating many origami fish models. It’s a versatile base that allows for creativity and variations in the final design.
If you are familiar with basic folds, you may find it is two rabbit ear folds.

Video of Fish Base
How to make Fish Base
Step 1
Start with a sheet of origami paper positioned like a diamond. Fold it half along with the dotted line, then unfold it.

Step 2
Fold the right top edge of the paper to meet the center crease. Then unfold it.

Step 3
Repeat on the left side. Then unfold.

Step 4
Fold both sides of the paper down to meet at the center crease. Fold the flap to the bottom and flatten paper.

Step 5
Sharp the triangle in the center.

Step 6
Fold the triangle down from right to left.

Step 7
Fold the left edge diagonally to meet the center crease and then unfold.

Step 7
Fold the right edge diagonally to meet the center crease. Then unfold.

Step 8
Fold the bottom point up along with the valley creases created in previous step.

Step 9
Fold the bottom point up along with the valley creases created in previous step. Then fold the flap down from right to left.

Step 10
Flatten the flap to finish your fish base.

Now you have finished this easy fish base. You can go to explore the following basic base in the world or origami or find some lovely moulds to start folding.