I've worn corrective lenses since grade school. I don't remember when I first started, but I do know that my younger sister had glasses before I did. I'm extremely nearsighted. Everything further than 15cm (6 inches) away is out of focus. I normally don't think much about my glasses. They're second nature, I put them on the moment I wake, and I take them off just before I go to sleep. Occasionally I'll remember that they're filthy dirty, and will clean them. With a two year around, they do tend to get smudged up pretty badly though.
The only times when I'm acutely aware of my glasses is when the frames are bent out of position. When the lenses aren't adjusted properly, the lenses don't focus properly, which can cause discomfort, and potentially severe headaches. This of course, always seems to happen about ten minutes before the local optical store closes, when it's a fifteen minute drive.
Needless to say, I've gained some experience in getting things mostly right. Never quite exactly right, mind you. Just mostly right. Enough to quell the oncoming headache, but not enough to get rid of the intense feeling of unease. Usually this just involves bending the frames back into position, although I also have a tiny screwdriver set to tighten the screws on glasses. Thankfully, I don't need to get that out often.
I've thought a few times about contacts, but I have trouble enough with eyedrops. The thought of anything near my eyes just creeps me out. At times when my lenses are askew, it almost seems like it might be worth a try.