Pretty grim. Sometimes if you let dry out you get lucky? If not hope you had good insurance on it. The cell phone people will not cover "washing". Good luck.
If your sticker hasn't changed color, you may be able to get it replaced. If not, take the battery out and let the phone sit in a bag of rice or grits over night.
You can't "fix" it.
If it dries out, it might work but if not, dont take it to the service store. They can see a little dot that turns red/or white when it gets wet. They can tell its water damage. They wont replace it, and wont fix it. They will make you cover either all the cost or if you have insurance they will make you pay a deductable.