I have taken a lot of pictures, because I'm not sure that my english is good.
First you take the blue fabric and cut it in long pieces. About 10 cm broad and 30 cm long. (4 pieces) and 1 piece about 35 cm long.
Stitch them togheter.
Turn the stitched pieces inside-out.
Make 5 long pieces.
Cut 2 round pieces out of brown fabric (or green).
Put on a brown piece al 5 blue pieces. Make sure that they are al inside. Just the end of the blue strokes can be outside the brown circle.
Put the other circle on it. Make sure there are only 5 blue pieces visible. You can pin them together so they don't move a lot.
Stitch al the pieces together. This is a little bit hard to do. Don't get nervous. :-D
Let one side open between 2 pieces, so you can turn the whole thing inside-out.
This is how it looks when you turned it inside-out.
Cut 5 pieces of iron wire, like 12 cm ( a bit longer than your blue pieces). Put the wire in each stroke. I pushed the wire on the end trough the brown fabric and folded 90 degrees so it doesn't come back.
After pushing the iron wire into the blue strokes, fill the brown fabric with soft filling.
And then close it by sewing it with your hands.
Make a knot with the longest stroke.
Now you need a fish. I took orange fabric. Draw a fish on the fabric and cut it out. Then you draw it again (same shape) and also cut it out.
Stitch the both pieces together, but not completely. You must be able to turn the fish inside-out.
Then fill it with soft filling and sew it completely now.
Put 2 nice eyes on the fish.
Stab a thread through the fish. Search a good place so the fish hangs horizontal.
Now hang your fish in the bowl.
Keep the cats away... :D