When I had a pool, I purchased a small trash can on wheels. Drilled a few holes in the bottom for drainage. You can paint it to match your decor. At the time, buying materials was far more expensive than purchasing a $10 refuse bin.
Here's an idea using pvc pipes:
You could try this neat pallet idea: https://www.ahs.com/home-matters/quick-tips/pool-storage-ideas/
Here's a few more ideas: