A few things I have found to be key:
1. Take care of hands and feet every night. Get some heavy duty balms/creams. Cracks are not fun!
2. Double bag your sleeping bag and a set of warm clothes because you never know what can happen... every flip I've seen has resulted in wet gear.
3. Get a guidebook for just her so she can follow along and be part of the logistical process.
4. A sarong is a great thing to bring. Makes changing/bathing more discrete and is comfy to put on after getting off the boat.
5. A FUD (Sani-Fem Freshette Feminine Urinary Director at REI.com
) is great for using 'the facilities' too. I wouldn't be caught on a trip without mine!
6. Something to spice up room temperature water (Emergen-C, fruity herbal teas, etc.) and drink lots of water.
Hope that helps!