You never enabled Android Device Manager (which is built in)? If you did, and if you have a mobile data connection, then you may be able to locate it.
If you haven't enabled ADM or if your mobile data is off as well as the WiFi then your only hope is to work out where you might have left it, go back there with another phone and see whether you can hear it. And hope you guess right.
You can install tracking software remotely (if you have a data connection), but you won't be able to activate it without access to the phone (it used to be possible, so you may find old webpages talk about an app called "Plan B" that worked this way, but it hasn't worked for the last 4 years).