Vostro 1x20 Water Resistance

first think to do is unplug the laptop and remove the battery asap, then turn it upside down

 

That's only if there are no drain holes like in Lenovo's Thinkpad.

 

As stated before turn it off (do not bother shutting it down, hold down the power button and force it off), unplug it, and remove the battery. I would advise NOT tenting it as you don't want water to go up over the lip of the keyboard accidentally and into the sensitive electronics underneath. Instead I would remove the keyboard completely. If you only spilled water, take the keyboard to the sink and dump it off. If you spilled anything else I would again take it to the sink, but rinse it off completely. Afterwords allow it to dry completely (overnight is usually fine, but I have found putting it in the oven at LOW heat works too if you're in a hurry... you're mileage may vary though) before you plug it back in.