I’m the paper and pen type to start.  I go through a lot of ink in my fountain pens, and I can go through a lot of legal pads when I brainstorm.  I can be out at a restaurant and have an idea, so I might scribble it on a paper or a napkin or make a note in my phone.  If I get an idea or an inspiration, I’ll make note of it somehow then transfer it to my brainstorming file as soon as I can.   I’ll have a lot of notes and ideas all over the place, then I’ll try to do a handwritten outline of the story and a profile of the characters that are more organized.  After that, I’ll put everything in a nice neat format on the computer.