|Your brain will often try to convince you that what you're seeing outside is THIS spot on the map, and you'll try to prove it, oh there's a small town left of it, oh that road looks a little similar.... Don't fall for that, VNC/VTAs are extremely precise regarding shapes of roads, large towns, bodies of water etc.... sometimes try to tell yourself: "maybe I'm not here", and look outside of your focus point. I've often fallen for that.
You should know what speed you were going (ground speed) so you know if it was faster than you planned or slower, that should help figure out if you should look ahead or before where you 'think' you are. Also a great tool to use is a VOR radial check, one VOR check will help you pinpoint where on your track line you should look at, two will help pinpoint a little more accurately by crossing radials, if you're lucky to be in a region with multiple VORs and/or good enough reception. Obviously, make sure you're competent enough using a VOR, if you're not, you may confuse yourself even more and fixate too much on your instruments and avionics instead of flying the aircraft.
One thing I did during my training when I was pretty lost, I pulled up my phone to see if I had reception, and opened Google Maps , waited for it to calm down as it was freaking out initially as the last time I opened it was 200NM away maybe. Then it would show me somewhat where I was..... I confirmed this on the map (VNC/VTA) with what I saw outside. This was a last resort. I did it twice I think
As stated above, follow your track with your finger, maybe mark a notch every once in a while so you know you've passed that part, so if you go back to the map without a finger stuck on it, at least you know which part of the track you've passed.
Small tip, many towns have huge water towers with the name of the town written on it, I did that once on a diversion exercise during PPL, not conventional, but it worked. Flew low enough to read it , but safe enough from obstacles and obviously abiding with CARs, if you have to skim the side of the town so you're not flying too low right over the 'populated area'.
Another thing you could do VFR, is just look around for a massive body of water, or highway, that'll often be easier to pinpoint on your map rather than a small town with a tiny road intersecting near a railroad track. Flying higher altitudes makes navigation easier, but adjust your speed in your head as to how fast you cross your track on your map with your finger, the climb may be slow but then things could speed up dramatically once in cruise, winds aloft permitting. Also you see a lot farther at higher cruising altitudes, I found navigating a lot easier than down low, I often chose a higher altitude if WX and winds permitted, and obviously if it made sense for the duration of the flight.
Conclusion for my disorganized rant, just look at the bigger picture instead of fixating at a small spot on map trying to convince yourself that you're there.