You should look for sneakers that are comfortable, great quality, look apealing (to you), ones that you can wear with almost anything. And overall the general benefits of the sneaker themselves.
Make sure you buy shoes that have good ankle, heel, and arch support. Also, be sure that they are the right size and do not rub, scratch, or squeeze any part of your foot.
Shoe shopping can be quite difficult, unless you know what you are looking for. The best advice is to buy what is comfortable for you. Supportive soles, and your style.
Look for comfortable shoes with good arch supports. Everyone always loves sneakers that look trendy but don't realize that they are not very good on your feet and will cause you to have problems either now or later. Once you've found good sturdy shoes then you can choose a design that you think is trendy or that you like.