People keep asking my opinion on binders and how to measure. 

My favorite binder was the Tri-Top (style 983) from Underworks.

Size - fits Chest: 
X-small 28-30 
Small 31-33 
Medium 34-36 
Large 37-40 
X-large 41-44 
2x 45-48
3x 49-52 

Be sure to measure accurately. It’s not safe to get a binder that is too small. Your shirt size might not be your binder size. Be sure to measure. It’s very important!!!

The best color to get is white. The white binder won’t show through your white t-shirt (depending on how thick the tee is) and can often pass as a white tank top.  

Disclaimer: This is all in my opinion, of course.