Use pruning shears to prune any branches that hang over the pool. Keep any other trees in the yard pruned according to their species requirements to minimize leaf fall. Pruning off broken twigs or branches will keep them from ending up in your pool.
Rake the yard regularly to prevent the wind from blowing the debris into the pool. Bag the leaves or put them in a compost pile.
Install a mesh pool cover designed specifically for keeping leaves out of the pool. Some covers go over the winter cover and others go over the pool by themselves. The stand-alone covers can come off every day. Install them according to the manufacturer instructions.