Before Anything Else, check to insure that the “Find My iPhone” App is installed and activated on all your devices, this means that you have signed in and activated your devices Location Services.
As soon as you realize that your device is missing, search the immediate area where your device was last seen; ask bystanders and clerks, watch for suspicious behavior and check lost & found (if nearby). Now immediately seek internet access, by computer or Apple Device and quickly check the last pinged location of your device, (online, the website to access the locator is icloud.com). From the App or website you will also have the options of erasing, locking, or causing your device to ring loudly. I must caution that if your device is in the hands of a thief, this may cause them to destroy it!
If you believe that you can reach the location your device was last “pinged” at (where the locator dot last was shown), proceed there with all due haste. Keep in mind that you will need a portable internet source of some kind so that you can track your device while on the move. Tracking the devices movements or location by vehicle is advised, and also that you have at least one or more other people with you, who have their own phones in order to contact the police if necessary. The Police/RCMP are very limited as to what they can do to help, unless a thief confesses, or the device is publically accessible (such as a ditch or dumpster), or someone is under threat of harm.
DON’T GIVE UP! You may be searching for hours or even on multiple days, but if your device has battery power, eventually you’ll find it – So stay positive! Even if it stops transmitting, a careful search of the last area it pinged in may turn it up. Awareness and calm are your greatest assets. It is very important to note that you should not go into strange or potentially dangerous areas by yourself, always take at least one friend as well as notify others where you are going and why. Approach any possible thief with great caution and strength. Be point blank in asking for your property to be returned. Speak loudly and if you can attract the attention of bystanders or passerby’s, do so! Do not be fooled by immediate denials of thievery or proclamations of innocence, usually the more loud the response, the more likely they are guilty. Innocent people should usually work with you to discover the truth, rather than argue. Be firm and polite, but don’t threaten. Protect your own safety to the utmost and be especially aware if you are dealing with more than one perpetrator.
I have directly applied these techniques in recovering my iPhone 5. I do not take any responsibility for the results of using my advice here and you follow any of these suggestions at your own risk! I personally believe that these techniques are one of the best options for recovering your stolen or misplaced Apple device. Good luck and be safe!