Ok there are five buttons you need to use
up arrow-move plane downward
down arrow-move plane upward
right arrow-speed up
left arrow-slow down
ok what you need to do is get your speed in the blue part on the very right gague. once you are going that fast you can pick up water. to pick up water you need to go down on the water, not too fast and skim over the top. if your nose dives under the water you crash. so keep it steady.
you have to avoid the birds, as they will also make your plane crash. using space to drop the water you have picked up, try and get close to the tree tops as it will put out more.
hope that helped. it keeps the bordom away when you are really bored.