This was a quick sketch of the tools I use: Staedtler and also Derwent Inktense watercolor pencils, a Koi pocket field sketch box of watercolors, a Kuretake watercolor brush pen, a DaVinci #8 watercolor brush and my favorite pen is a simple Uniball vision fine point black pen.  I make a card displaying the colors that are in the sketchbox so I know which colors are which.