I did two treks with my son. Adult advisor on the first and on vacation for the second. Other that the standard, remember you are on vacation and let the youths lead, my biggest tip would be to make sure you are packed up and ready to go before the yutes. On our first trek, we had a sister crew from the troop and one of the adults was the last to get ready almost every morning. From what I understand, everyone else would be standing around waiting while he doctored his feet, fussed with his pack, etc. It took several talks from the adult advisor and the youth crew leader to get the adult to better manage his time in addition to getting called out during Roses, Buds and Thorns.
Is your step off date on Tuesday? It won't help this time but it might be something to think about for future crew treks. We selected treks that started on Tuesday, but we left Houston on Saturday morning. We stayed a night in Amarillo at the Kwahadi Museum and then 2 nights at the NRA Whittington Center in cabins. We used all that extra time to do hikes at elevation around the Capulin Volcano crater rim and in the WhC back country. On that Monday, we did about 13 miles at the WhC with full packs and did a meal cook using similar items in the PSR meal kits as a final shake down.