My little brother accidently poured water on my laptop! now it wont turn on what do i do?

Keep it in a room temperature location for a day or to and try again. f iyt still fails to start, you have a seriously damaged computer--requiring techshop intervention or a new system.

I would automatically suspect that when you tried to power it up, the motherboard had a short and fried. If that did not happen and there is just a grounding issue with the fluid, then I would suggest a complete teardown of the laptop along with extensive drying of the parts with a hair dryer and then all the parts need to sit out for a day to make sure there is absolutely no fluid or condensation in any small groove, space or hidden area. Below is a tear down and service manual for the Aspire One. Good luck.

http://tim.id.au/laptops/acer/aspire%20one.pdf