definitely one of the glide products.
and, Gold Bond food powder. It's amazing stuff. And I use it all over my body, including my dog.
It keeps moisture away.
Clothing
Lululemon (http://www.lululemon.com/) clothing. Totally worth the extra $$. They're made not to chaif, and they have great sizing.
Go with longer fitting (more of a crop pant) that's breathable, but will hold everything in nice and snug.
AND
MEC - http://www.mec.ca/Main/home.jsp
I find the cheap (old navy, walmart, target) stuff doesn't keep it's stretch or tightness after a few washes. Waste of money. And I don't even bother buying the crappy clothing anymore.
Hydration, I've been drinking a bottle of G2 (the gatorade low cal stuff - http://www.gatorade.com/default.aspx#product?s=g2) just to ensure I'm getting electrolytes. You could also go with Pedialyte (http://pedialyte.com/). It's made a world of difference.
BIG BIG difference, actually. No more head aches & I'm not very lethargic anymore.
Because I can't drink a tone of water anymore, without getting the burbs badly, I rely on this stuff. Just make sure you go with the lower sugar stuff & not that vitamin water, that's full of crap.
Also, invest in one of these.
A hip pouch that can carry water. I use this one.
http://www.mec.ca/Products/product_detail.jsp?PRODUCT%3C%3Eprd_id=845524442621094&FOLDER%3C%3Efolder_id=2534374302700103&bmUID=1279206856847