Fooo346 generously braves the rain to demonstrate how to use buckets for us.
Buckets.
Regular players are not able to use buckets for good reason; grief prevention. Bucket use is available to those players who donate 25 dollars or more. Non-donators are able to purchase water and lava blocks from the market if they would like to be able to place them themselves. Otherwise, you can always ask a donator nicely if they would kindly assist you.