My biggest problem is work, as that is the one thing that I do most of my waking day (duh for those of us that are not retired!). My types of work is extremely hard on my eyes (auditor), and causes a lot of fatigue. I use lots of lights, I have my font extra large. These seem to help. I also try to always get adequate sleep.

 

My greatest fear is that I will 'burn out' my eyes while working and not be able to do the things I love and enjoy my time during retirement. That would really be a bad thing.