The important thing to remember is that every portrait tells a story about the subject, and because each subject is different you'll need to adapt the way in which you approach each subject.
It’s a good idea to talk to your subject first and get an idea of who they are, what they want their portrait to look like or what you want to portray.
What's on trend with Portrait photography? The timeless soft-touch or the classy black-and-white. To the modern montage theme, to even what is considered a good crop and a bad crop. Take your pick or try them all out.