I think the easiest habit for me out of the "7 1/2 Habits of Successful Learners" is, of course, number 7 1/2: Play!
The most difficult for me to achieve will be Habit #3: learning to view problems as challenges. I get frustrated easily and tend to fret if something unexpected happens, or if something I thought would be easy turns out to be hard. Things that I know will be hard I face with extreme procrastination!
This also ties in with having confidence...I believe that by gaining more confidence I will be able to view myself as capable of surmounting challenges.