How to choose perfect eyeglasses frames

[glasses store]

There are kinds of glasses frames separating by different colors and shapes on markets nowadays, and the price in online sits is much cheaper than those in local stores, that's the reason why I always choose online shops, however, not everyone has a clear mind of choosing a perfect pair, someone need the trend, and someone need its durability, and others may be more inclined to comfort, so, anyone who have much experience of shopping online can give me a piece of advice?