As people age, they often develop presbyopia, the inability to focus on things close at hand. Bifocals are meant to correct this, but many people find them disorienting or excessively expensive and choose reading glasses instead. Drugstore reading glasses cost less than $10 on average and come in a wide variety of strengths and styles.
Consider going to an optometrist or ophthalmologist to get prescription reading glasses. Most people require slightly different lenses for each eye. Over-the-counter reading glasses do not correct for eye differences or common vision problems such as astigmatism. These one-size-fits-all lenses can cause eyestrain and even headaches.
Pick out a pair of glasses at a strength you think might be right. Reading glasses in pharmacies are usually sorted by strength. Don't worry about finding a pair you like yet--as long as it fits you reasonably well, it will do for the moment.
Get a magazine from the magazine rack or a book from the checkout aisle and hold it the way you usually do when you read. If you like to read lying in bed with your book right in your face, for example, hold it right in your face. Try reading it and notice if the words are blurry.
Try on a stronger pair of reading glasses. Are they better or worse than the first pair? If they are better, try on an even stronger pair. If they are worse, try on a weaker pair. For example, if your first reading glasses had a strength of 1.00, try 1.25 glasses. If they work even better, try 1.50. Keep trying on new glasses until you find the best strength for you.
Once you find the right strength of reading glasses, pick out a style you like. Reading glasses come in full-frame styles, which cover your whole field of vision, and half-frame ones, which only cover the bottom. Full-frame are great for looking at things very close up, but they don't let you look into the distance clearly. If you are going to be switching your focus between near and far objects, get the half-frame glasses. If you are only going to be concentrating on what is right in front of your nose, use full-frame ones.