People who wear glasses have several options, such as masks with corrective lenses built right in. When buying any diving equipment, the most important consideration is comfort and fit. Be sure that your mask is the right size and fits your face well. The Snorkel Snorkels come in a variety of shapes, sizes, and with fancy gadgets. Things on top of the basic snorkel are bells and whistles, but they may add to the comfort and fit.
Several snorkels come with purge valves near the mouth piece.
Therefore, you don't have to use as much energy clearing your snorkel since the water will exit the valve as well as the top of the snorkel. Typically, silicone mouth pieces will be most flexible and comfortable, but will cost more. You get what you pay for. Finally, don't use a fancy device to snap your snorkel onto your mask. This basic rubber band-like device will keep your snorkel in place and reduces the chance of you losing it.