Might be stating the obvious here but my biggest lesson was learning to use my non-preferred eye. My natural sighter is my right eye, I use it to wink, site a rifle, it is my primary seeing eye when I'm talking to someone and it was my natural ep eye when I first started observational viewing, but it's not my best eye. I have been told it's 18/20 due to some metal that got lodged in it when I was 21, the metal had to be scraped out with a scalpel and it has never been the same. My left eye is 20/20 and I use this eye for all my viewing, even if it doesn't come naturally and still feels uncomfortable after extended viewing. The problem with using my secondary eye is that while it might provide clearer vision it was much weaker than my primary eye, so I needed to train it and develop it. My first reaction is still to look in any ep with my right eye, but it's important to know your best eye, or pick your best eye for the best results.
Strange but true.
