You will need:-
some cardboard from the recycling, or a pizza base.
A bit of wool or string.
Here we go!
Draw a spiral shape from the edge of the circle, I imagined a coiled-up snake, then when you reach the centre you need the round off the end of the coil.
Make a small hole in the very centre of the rounded off part in the middle. Then you need to cut on your spiral markings all the way to the middle.
Paint the whole of the cardboard, I did two shades of bluey-green, one shade on each side. I had to wait for each side to dry before I could do the other one.
Then decorate one side - I did mine with splodges of different coloured paint and I sprinkled glitter onto the wet paint. (Make sure your glitter is from previous years, like mine is, or buy eco glitter so as not to cause harm to sea life when the glitter finds its way there).
Leave it to dry.
You can now decorate the second side, I put little dabs of glue and stuck some stars onto it. When it dries, thread your string or wool through the hole in the middle of the circle and hang it up to sparkle!!!
See where your decorations go, you could do stripes of paint, or stick foil milk bottle tops onto it. Maybe make one in Xmassy colours, or crisp winter colours, have fun!