So, I cribbed a page from David Lobenberg, and tried a long and narrow format. Yes, it's imitative, yes, it's unoriginal, but I was inspired by his post of watercolor sketches he did in this remarkably long sketchbook, and by this cool (long thin) painting on Moments of Clarity.
I don't have the actual long format sketchook that David used, so I drew a thin rectangle on my little moleskine watercolor book, and used little, tiny brushes. This thing's about three inches (7.5cm) wide and seven or eight inches (23cm) tall.
Since I'm a noob at all this, I've not tried anything larger than the moleskine yet, but I'm beginning to get frustrated at the size of the page. Yes, they are very convenient for: a quick sketch; schlepping your gear around the countryside; and curtailing those feelings of excessive grandeur that might arise from having a great big sheet of paper to despoil (if said feelings aren't pre-empted by anxiety about despoiling a great big sheet of paper... but let's give oneself the benefit of the doubt, and assume one can approach the prospect with confidence.)
Joking aside, I was also led to the composition by the landscape in front of me: clustering clouds, springing up in the humid afternoon air over the mines in the distance. I wanted to do a panorama, but my locale (and time of day) didn't lend itself to anything dramatic. The colors were beginning to wash out and the sun was approaching noon, which made the shadows on the mountains flat. The most interesting thing to me was the sky, so I figured I'd feature that.