Palming is good for relaxing your eyes and avoiding the stress that causes further vision deterioration. However it wont really enhance your eyesight as a standalone exercise. For that you also need eye strengthening exercises.
I began eye exercises last July and they worked great for me. I could see the difference within the first week. Several weeks later I went to my eye doctor and she cut my prescription from -3.25 to -2.25 (I had myopia). Another few weeks and I was measured at -1.75 and completely lost my astigmatism. To me that is a pretty quick result!
To speed up the process towards the end I also wore pinhole glasses
15 mins a day while watching TV.
It takes commitment, but IMO eye exercises will work for most people with typical refractive errors of the lens. If you're that desperate to get away from glasses - eye exercises are worth the effort. Check out the website I made after doing eye exercises and the difference it made to my life: Improve Vision Naturally: Improve Your Vision with Daily Eye Exercises
It's your call - and your commitment - I just want you to know that there is an alternative to surgery or contacts and you do have the power to fix this yourself.