This takes about ten minutes a day and one decision made early. That is the whole plan.
Most grooms do nothing until the week before, then do five things at once. That is exactly the wrong order. Here is the short version.
3 months before: If you have acne or heavy marks, start now. Same rule as anyone else — twelve weeks to see a result. 6 weeks before: Decide the beard shape. Growing it out or shaping it down both take time. 3 weeks before: Trial haircut. If it is wrong, it grows back before the wedding. 10 days before: The actual haircut. A fresh cut on the day looks like a fresh cut. 5 days before: Beard shaping and any threading. Not the morning of. The day before: Sleep. And do not try a facial you have never had.
Wash your face twice a day. Not with soap. Moisturiser after shaving. Every time. Sunscreen if you are outdoors, which during a wedding you will be. Do not have your first ever facial in wedding week. That is when reactions show up.
A haircut done two days before that sits too high and too fresh in every photo. A first-time facial or bleach in wedding week that leaves the face red.
Haircut ten days out, trial haircut three weeks out. Beard shape decided six weeks out. No first-time treatments in wedding week.
About ten days before. A cut done one or two days before looks sharp-edged and unfamiliar in photographs. A trial cut three weeks before is worth it if you are changing the style.
Only if you have had one before and know your skin handles it, and no closer than ten days to the wedding. A first-time facial in wedding week is a genuine risk.