A kisser button goes on the sting and at full draw you should feel the kisser button on the corner of your mouth. I have been using one for years, it gives me a more constant anchor point every time.
I am 46 and my eyes aren't the best, I do where reading glassed and have for the last two years. I shoot with contacts 100% of the time glasses don't work for me when shooting my bow or hunting.
I went with a 1/4 inch peep and smaller pins so I don't get that hallo effect as bad. I also shoot a Black Gold site, I like the way this site does not make the pins so bright when shooting in sunlight.
I will be working on shooting with both eyes open to see if the helps.