I've done this for years to keep my outings better organized. Hope it helps. Preparation always helps things go a bit smoother.
#1 - determine from the pro shop about three weeks or so prior (if you don't know yet) if you're simply going out in straight tee times off the first tee, or being shotgunned on different holes at the same starting time for every group in your outing. If they tell you straight tee times, everyone starting on hole1 - find out what your first group's starting time will be. If they tell you that your group will be shotgunned - find out which holes your group will be starting on.
#2 - determine the pairings well ahead of time. Send out an email or group text to let everyone know what the pairings/starting times will be for each group. Do this a few weeks out so you can make adjustments if needed. Otherwise you're going to possibly have one guy wanting to play with another guy from a different group at the last minute, which will screw things up with the official scorecard preparations.
#3 - on the day of the outing, get there a few minutes prior to everyone else so you can go into the pro shop and fill out the names on what will be your "official" scorecards for each group. I always use "last name, first name" in the player names section on the scorecard. That way if you have players with either the same first names or same last names - you're removing confusion. Also... if it indeed happens to be a shotgun start - take a highlighter marker and highlight the starting hole on each scorecard for each group's starting hole. This will help insure that they don't start marking their scores in the round on the wrong hole on the scorecard. If it's just straight tee times on the 1st tee, then simply mark the group's official starting time somewhere near the top of the card, just so they're aware that they need to be ready to put a peg in the ground at the according start time on the first tee box.
#4 - communicate to your players that each of them will need to "check in" at the registration area as soon as they arrive at the course. That's where you (or someone) will collect the outing fees and skins money, give them their pairings sheet (which also details the competition rules for the day), and scorecards. Remind every player that as soon as they're finished with their round, the group scorecard needs to be turned into the pro shop immediately afterward.
#5 - you might ask the pro shop to do the skins for you. Since there are no handicaps involved and it's gross skins - it'll be easy for them to do this, especially for only 24 players. Otherwise... collect the scorecards from the pro shop, right down each player's last name on a sheet of paper, and then have someone read off the lowest score on each hole. Ties obviously mean no skins. But for every player that wins a skin with the low score on the hole, simply mark it next to his name on the sheet to keep count.
In the rarest of circumstances you might have a situation where no skins are won. I've had this happen before, believe it or not. In that event we simply take all of the skins money and put it on the bar tab, OR... give each player back his 10 bucks (or whatever) that he paid during registration for the skins game.
It sounds like a lot of work, but it really isn't. The hardest part is in the preparation prior to the event. But keeping it organized will make it a lot easier for you (or whoever the outing coordinator is).