My very first manuscript published in Physical Review Letters (major physics journal!) came about by drawing figures on piece of papers (basically mocked-up figures) with a colleague of mine!
Both of us were PhD candidates and attending a conference where new nuclear collisions analysis techniques were presented. As we were listening, it became obvious to us that we could used a combination of these new approaches to tackle an interesting and unanswered scientific question for which we had just started to analyze the data. It also turns out that this particular data sets had key features that enable this specific analysis. Without getting into the boring details, when we got back to the hotel room, we had this terrific discussion during which all four figures of that manuscripts were done with pen and papers i.e. what they needed to be (variables to look at) and what analysis was needed for each of them. We even went as far as sketching what the results should be based on our knowledge of the collision…and it turns out to be mostly right 😉
We came back, enlisted the help of a summer student (who is now a medical physics colleague!) and within a few weeks we had a draft ready. Not every paper is like this, but it does happen. Are you ready for it?