Watering the parasol

When at the beach, if the sand is too loose to hold up a parasol, pour water around parasol's base, which will compact the sand and will hold the umbrella more tightly

Backpack/Umbrella

If you're wearing a backpack, have an umbrella, and it's raining, wear your backpack on your chest so it won't get wet. If it's on your back it most likely won't get covered by the umbrella, or the umbrella-runoff will drip onto the backpack and soak it.