How do I fix my wet phone?

You did everything right up to the point of turning it back on (or rather putting the battery back in to try that)...

A phone (or any complex electronics) that has got any trace of water on the circuit board needs to be absolutely dry before power is applied again.

Because of the way surface mount circuit board are built, most of the components act as capillary traps and hold water between them and the board.

Areas covered by metal screening cans are the worst, as there is no airflow to assist evaporation.

From practical experience, it takes between one and two WEEKS in a very warm place with plenty of airflow to dry out a bare (uncased) mobile phone circuit board.

Rice acts as a dehumidifier for the air around the phone, but does not magically extract trapped water from beneath components.

Somewhere really warm with plenty of airflow is better than cold and in rice or a proper desiccant.

(A fridge will do no good at all and may cause more harm - things that have been cold get condensation on them - more water!).

Leave it (with the battery out) somewhere as warm as possible, but not so hot you cannot keep your hand in the same spot for several minutes.

Give it *at least a week* then try it. If it's in any way less that perfect, give it another week..

It's better to be without it for a week or two than permanently, which it the likely outcome if you try to use it while there is the slightest trace of moisture left in it.

You did all the right things you can do. If all else fails try putting it in the fridge for awhile. We've all done it before. Me a few times, after the rice & fridge, if you still get a black and flashing screen, you know what comes next. ..that's right, my crystal ball says, 'New Phone ' in your future!

Might be to late. You should have submerged it in rice and let it dry completely for atleast a day before you ever even turned it on again.