transcribing forms

I'm new at transcribing here and am wondering what to do with filled in forms that include blanks, i.e., a designated entry like "Year begun" has no entry.  Should I leave a space or [no entry]?  It's not a chart or table but I followed that model.  Also the typed entries switch from blue ink-ribbon to red ink-ribbon, back and forth.  Is it necessary to indicate those color changes also?  Thank you!  If it helps, I started one the last page of one of the inmate case files at Leavenworth Penitentiary.