In reply to mark mcgowan01:
I assume you are already booked into the Hornli hut? You need to book well in advance and there is no camping allowed near the hut.
The obvious thing about the route is its length. Most of it is a scramble. So, everyone needs to be technically competent at Grade II/III scrambling. There's been a lot of snow this year, so conditions may be more difficult than usual. There was snow and verglas on the upper section when we did it last year and that meant climbing in crampons from above the Solvay Hut. Someone once said to me "it pays to be as good as the mountain you are climbing". And, I think that applies to the Matterhorn.
You need to have your technical plan worked out for the upper fixed ropes: they are the big thick ones! Both in ascent and descent. Abseiling will be slower but safer than downclimbing.
The descent is what you would expect on a grade II/III scramble. Most of it is downclimbing with perhaps 10 abseils possible at various points. Because it's so broken, you'll never abseil more than 20m at a time.
The thing to avoid on the descent is veering right onto the East face, which is loose and treacherous. When we did it, there were light boxes on the route every 100m or so (which were lit up at night). They may have gone, as they were for the 150th anniversary last year.
Finally, on the descent I'd say "concentrate, concentrate, concentrate" and think about every foot step.
It goes without saying that you should do a shorter route first: the half traverse of the Breithorn can be done in a day from Zermatt using the early cablecar. If anyone struggles on the Breithorn, you shouldn't take them on the Matterhorn. And, the Allalinhorn is the easiest 4000er to get acclimatised first.
Pollux is another you can do in a day from Zermatt.