-Save often. It's easy.Starting Xenoblade probably in the next hour or so, please give me beginner tips, stuff that will save me grief, etc.
-Don't worry if you don't understand the combat immediately. It took me 6-7 hours to understand it, but I loved it once I did. You reread all tutorials in the game if you want to know something.
-All characters level at the same rate, so you could just use 3 characters for the whole game and still have everyone be the same level. I used Shulk, Sharla, and Reyn for 75% of the game, and it didn't get stale.
-Side quests, Gems, and affinity stuff is mostly optional. If you don't want to worry about them, then don't.
-Update your armor at least every thirty minutes. It's fun.
-Explore
-Stop asking questions and find out stuff for yourself.