Hello friends... a few quick questions.

A friend and I are in Chile, and have just purchased 2 Xt 600 e, years 99 and 04. Let me first say that we both know nothing about working on bikes. We are going to be traveling in remote areas on rough roads, and I would like to keep my bike in good shape so I can avoid problems. I am wondering if anyone can advise me on the basic daily weekly, monthly things I should do to keep the bike runnin well. Im thinking about basic upkeep. What pressure should I run the tires at, how often should I fill them, when do I put on chain lube, etc. etc. I am going to be changing the oil every 3000 to 4000 km´s but I am trying to get an idea about what I can do in between to help out. The bikes didnt come with a manual so I am kind of at a loss. Specific questions Im wondering:

1) I weigh 210 lbs and will be carrying roughly 75 lbs on the back... what is the proper tire pressure? How often should I check this?

2) How often do I need to put in new brake fluid, coolant, etc??

Basically, if you can give me advice on what to keep my eye on while travelling this will help a lot. Im gonna be riding this beast around south america until about may and dont want to get bogged down by little problems that can be avoided. Thanks so much