So, pretty much all restaurants have menus, and Chinese restaurants are no exception. Most of the time, they’ll have done a half-assed job translating dishes into English, beyond your standard Orange Chicken, Lemon Chicken, General Fuckface’s Special Sauced Chicken, etc.
If you want General Fuckface’s Special Sauced Chicken, etc., you’ll have an easy go at it. Naming conventions for American Chinese dishes are surprisingly well standardized across most of the country. There are some regional variations (e.g. General Tso’s versus General Tao’s), but, for the most part, Lemon Chicken is Lemon Chicken in Mississippi and Maryland.
On the other hand, if you’re looking to get authentic dishes, but are not able to read Chinese, you’re in a bit of a pickle. The easy solution for this (and many other problems) is to bring a (Chinese) person who frequents that restaurant with you to your meal. He/she will probably know what that particular restaurant does well, and guide your selection process.
If this isn’t an option, you’ll have to pull some more advance level maneuvering. Checking Yelp is a good idea, though not all Yelp pages are commented equally. Looking at the “Chef’s Specials” or equivalent portion of the menu is also a good, general rule of thumb. Probably don’t give too much credence to Daily Specials. Some restaurants use these specials to highlight fresh ingredients unique to that day. Others use them to dump shit that they need to get rid of before it really starts rotting.
Another good idea is to probably Google/Wikipedia the variety of Chinese cuisine served at the restaurant (i.e. look up Sichuan food if you’re going to a Sichuan restaurant). This isn’t foolproof – many times restaurants are just named Hunan [noun] or Sichuan [noun] on a whim rather than because of the food served – but it’s a decent starting point, and, perhaps, you’ll learn more about Chinese food in general.