BRING LESS USELESS CRAP! I know this sounds reactionary and over simplified but I have taken a few first timers and although they asked me what to bring , most showed up with way more than needed.
I would add:
1.A little travel bottle of shampoo. (its nice to feel human)
2.A travel bottle of dish washing liquid. (its nice to eat out of a clean bowl)
+1 on the baby wipes
