Sketch won't run

Using Arduino Project Guidance
5

UKHeliBob:
If the upload was successful then the sketch will be running

Put some Serial.print()s in the code at strategic points such as entry to and return from functions and print out the value of pertinent variables. Is the code calling the functions that you expect and are the values of variables sensible ?

Thanks, but first off , it is not my code but from here:

I tried this:

RTC.readTime();
sprintf(psz, "%02d", RTC.s);
Serial.print("Time");

But it didn't work, so I must have got it in the wrong place.

So I tried it here, but nothing printed out:
RTC.readTime();
sprintf(psz, "%c%02d%c%02d", (f ? ':' : ' '), RTC.h, (f ? ':' : ' '), RTC.m);
Serial.print("Time");

If you could point me to the right place please.