I ordered this in white in medium. It was really not big enough as I would like it. I can wear it but will probably give it away. In white you definitely have to wear a tank top or cami underneath. It is sheer, which makes it good for summer to cover your arms but still be cool.
I ordered it also in black in an XL which turns out to be a bit big but I will keep and wear it. The V neck is very low in the larger size so will also wear a tank or cami under.  You can wear the sleeves long to your wrist or roll the  m and button as shown in the picture, which is how I will wear it.
I would recommend ordering a size up. I ordered XL and I should have just ordered a L.  Be sure to order this shirt from a Prime source so that if you need to you can return it. The white one I ordered came from China. A longer wait and a more expensive return.
It is a nice looking shirt. But it is definitely chiffon.