A few days before the event( most likely one or two) depending on the event, I check if I can find everything we need. Now, keep in mind we are 5 in my family. If all goes well I find everything in order. In my family this is rarely the case. There is always something to be fixed and put aside to be fixed, which seems to get lost in the fray of every day life here. So off to check the Laundry baskets, the kids rooms, the multiple fix-it and sewing piles ( I always have a project going, but that's for another time), to finally find the item fallen behind a piece of furniture.
Once all our pieces of clothing are found, i make sure they are reasonably clean. Then I fix whatever needs fixing. One time I had to put back buttons back on a vest. I also check if it still fits. I have two growing boys of different builds, so it happens that they outgrow of their clothing. Usually there are tucks in waistbands and in the legs I can take out. If they don't fit we scrounge around for an alternative. These days thought, my oldest is starting to fit into adult clothes so I've modified some of my husbands clothes to fit him.
Then it's the hair's turn. The boys I generally don't have to do anything but a light brushing, my oldest keeps his hair short, but my youngest boy keeps it long so I try to convince him to pull it back in a ponytail. For my daughter nothing specific either. For myself, there is usually something to be done, for the most part i put my hair up in a bun, put on a day cap and call it a day. Other times though, I need to fancy my hair up, and do something completely different, which means research and trying it out before hand.
The day of the event seems like complete chaos (to me anyways). I lay out everyones clothing. There seems to always be the search for dark socks( we never seem to have them when we need them.) I often pack food and water. Pack any gear we have, such as demonstrations and any hand sewing I happen to have. And off we go.