أنشئ حسابًا أو سجّل الدخول للانضمام إلى مجتمعك المهني.
I think there is not easiest way i have one soloution for this by simply print a paper on which print setting highlight the setting like A4 paper margin and header by this your customer will done default setting when working on Excel and your problem will be solved Also first time you will be feel uneasy but again you will get free from this problem.