To make this, I first started off with plastic sound tubes like this:
I found that the kind that stretches out works much better than the sound tubes you swing in a circle because they are bendable and easy to work with. I found mine at FiveBelow. They were $1 each and I found them on the very bottom level of the bins near the register.
The first thing I did was stretch out the tube, and then I cut them to different sizes. I worked with one tube at a time that way I didn't mess up all of them at once by cutting pieces too short. For the blue and green coral pieces, I cut one longer piece at the hot glued the shorter pieces to that.
Not all coral is the same, so don't be afraid to bend the pieces and cut them all different lengths!
For the orange and yellow coral pieces, I cut the tube into pieces and then glued each of them to a sturdy cardboard base. These pieces of coral didn't look full enough to me, so I also coiled colored pipe cleaners around a pencil and glued them in between the pieces to make it a little more exciting.
After that, I took all of my coral pieces and hot glued them onto a piece of cardboard. The last thing I did was add a few more springy pipe cleaners to tie all the pieces together. Ta-da!