The only thing you can do is pull it apart and unhook the battery immediately and dry it with warm air. Don't charged it. Once it's wet it starts corroding immediately especially with power going through it. Clean any corrosion with a qtip and alcohol or a soft brush like a toothbrush. But the issue is that once it's been wet it's likely to cause issues and could stop working at anytime. Repair shops won't work on water damaged phones except to retrieve data.