This service is so worth for Apple’s devices owners like you because you can prevent something before it is too late. Therefore, here are some simple steps you can do, but before that you must require a MobileMe subscription.
First things first, you must register to Find My iOS device services (requirements applied) and set up free accounts for your iOS device that runs 4.2 version or later. Then, you should verify the software version of the device by navigating to Setting app and move to General => About and take closer look to Version.
The second step comes with two possibilities, if you already have a MobileMe account, you can skip this step, but if you don’t have the account here is what you can do. You need to go to Create Free Apple ID and follow the instructions you found. Normally, you will need to verify your new account by tapping the link included in the verification email sent to your email account used for your Apple ID.
Third step, after finalizing your account, you can test the Find My iOS device service by turning on the service. If you obtained your new Apple ID in step 2, the instruction will automatically lead you to this activation. Or else, you can go to Settings => Mail, Contact, Calendar and tap the MobileMe account. Then, switch the Find My Device. Once it is switched on and pick Allow, afterward tap Done.
Next step, you should test the service on the website by accessing your set-up device from computer or other iOS devices. You can check by accessing the www.me.com by typing the right user name and password. When the service has been set up, you can find the exact location of the device on a map through MobileMe’s web interface.