I have swum with a few cameras.
I have tried silica gel and rice - with little noticeable result.

1 - don't power any thing up.
2 - don't power any thing up!
3 - remove everything; cards, batteries, etc
4 - as per 'flipperfla' - if dirty or salty water - rinse well.

5 - I hung my drowning babies over a wood stove (as in steel box - NOT an open fire) with a medium to warm heat. Lens down with all 'doors' open. Left them for several hours. Unless there is electronic damage it should work. should?