My simple understanding of the rules when I came out of initial training was that pilots flying VFR will navigate using visual references on the surface while pilots flying IFR will use VOR's, NDB's etc. However, when I think back to the rules in the ANO (what a horrible read) they don't state anything about how one is to navigate, just rules on the visibility and the compliance with clearances etc.
...and you are quite right - using your "own navigation" its often called. That is a fundamental principle when you train for a PPL when instructors will also add in VOR's and NDB's for you to nibble at in your subsequent X country tests. IFR is another matter altogether but always remember that ATC is there for PPL's or anyone under training. You will certainly be asked by someone at some point "where am I?"
Hope all goes well for you.