Can't Resist the temptation to repeat the famous quote from one particular USAF pilot
" You have never been lost until you have been lost in an SR71 Blackbird"
Actually its "You've never been lost until you've been lost at Mach 3". The point being that a standard rate turn at Mach 3 has a radius of something like 100 miles.
On the thread topic, really the answer is you shouldn't be out on your own until you CAN'T get lost. Even without GPS you have VOR, DME, ... and of course you DO have GPS (or if you don't then you're choosing to get lost every bit as much as if you took off with no charts). But even without GPS, assuming you keep a VOR tuned, better yet two of them, and keep an eye on them, you will not get lost.
Of course if we are in our mythical no-electrics Piper Cub or Tiger Moth, then you'd just better be paying close attention to roads and railways. Bodies of water are about the most helpful thing, in England at least. (Here in California we have mountains which make it a lot easier to figure out where you are, though also a lot more important).
n5296S