Can someone please explain this sync thing!

Oh my goodness. I'm so lost. I guess too much caffeine and the jitters are getting me!

Anywho's I'm just trying to get MobileMe set up. Every time I go under system preferences/.mac to sync it gives me a number of conflicts. The latest problem (which has actually happened to me three times) is that when it's done syncing all my bookmarks are way messed up (duplicate bookmarks, misplaced on the bar, etc.). In my calendar there are duplicate events (parked right under each other) and weather calendar for each day that I deleted a year or so ago?

Plus to add insult to injury I can't get the contacts or mail to push like it should. What am I doing wrong?