You have received many clever responses to your enquiry thus far…I will respectfully advise you that you will risk receiving some inapplicable information unless you specify what material your eyewear lenses are fabricated from.
I do not personally know of anyone who is using glass as a choice for their refractive eyewear, so, I’ll wager (perhaps incorrectly) that your eyewear has lenses that have been fabricated from a polymer material (a “plastic”), and likely either one of the common CR-39, Polycarbonate, “Trivex”, High-Index or Ultra-High Index materials. If this is the case, and if the lens has shallow (absent of raised edges) scratches, and if they have no coatings applied to them, then I would recommend that you use the “3-step” NOVUS plastic polishing compounds, which you can apply by-hand and which you do not need any special training or equipment…simply follow the instructions. If you are interested then you can learn more about NOVUS polishing compounds at: http://www.novuspolish.com/
you can buy some spray to spritz on lenses and wipe with a soft NON ABRASIVE cloth It is made specifically for this purpose check isles with the contact solution or ask the pharmacist you can even purchase at your local eyevision place I do believe.