The bowl of rice myth is quite popular.
Speaking in general, if it has a battery, the best thing is to remove it A.S.A.P..
Once all power is removed from the device, disassemble and dry it out with moving air. (such as a fan)
It's the gaps and places you can't necessarily see, that take the longest to dry out. So take it apart s much as is reasonable in order to effectively dry the device.
After drying for at *least* a full 24 hours in moving air, check for and remove any hard water deposits and debris (including chemicals) left behind by the water. 90% isopropyl rubbing alcohol can be an effective cleaner. However if the board has a protective coat against water, (which is rare,) the alcohol may remove or damage that coat. Rubbing alcohol may damage some components, such as flexible PCBs; so its use should be carefully considered.
Inspect the battery and replace if swollen, leaking or damaged.
Try to power up and test device. Corruption can make it necessary to reset it.