how to find my iphone 4's problem is my i cloud is on but find my iphone is turned off. iv'e been trying everthing i could think of. Need some help from the people out there that no what to do
If you did not turn on Find My iPhone on the phone before it was lost, then I'm afraid that you can't find it using Find My iPhone.
You can't turn it on remotely, as this would be a huge privacy issue.
It's a bit like having an insurance policy - you take the hit up front (by buying the insurance, or by turning on Find My iPhone), and it pays off later (by providing coverage, or telling you where your phone is). If you don't do it up front, then you lose.
Sorry, but I don't think it's possible.
Your best bet would be to contact law enforcement (in the case the phone was stolen), and see if there is anything they can do. If the phone was simply lost, then I am pretty sure there is nothing you can do about it, other than send it messages and hope that someone finds it and responds to the messages.