How to treat cracky voice

Many Gospel ministers do complain of their voice do crack....
So we are going to be treating on that
First the causes:
1 over usage of your voice
2 dehydration
3 shouting

 So what do we do

1)We try as much as possible to avoid shouting and drink a lot of water
2) when you feel strain in your voice don't sing just take a nap and relax..