How do you make a server on the AT-Laucher on a Mac?

How do you make a server on the AT-Laucher on a Mac? I would like to make a server for the Hermitcraft Modsauce Modpack but I only have a Mac. So I would like to know it there is a way I can make a server on my mac and if you can make a server can someone please tell me how to make one. I know that it is possible to make a server on a PC but again, I only have a mac. So can someone please help me? If anymore details are necessary please tell me and I will try to give you the information.

If you are using one of the offical packs there should be a button on the side along the same area as the install button. Clicking it should create a server file IF the modpack has a public server files option.