I think it's good to use as minimal a set up as possible, you'll certainly want to be light during a long day of sketching and you'll need to draw and watercolor often standing ... not an easy thing to do. So light and easy it's good.
I use mechanical pencils for drawing, any type works for me.
The water brush pen is the key to quick and easy on the run watercoloring. It's just a brush pen that contains water. There's a couple of different brands making these but they all work fine ... You can buy them at Japanese Bookstores like Kinokuniya in a few cities around the US. If you're in Japan Tokyu Hands has them.
Any decent watercolor set will do, I have a Windsor and Newton set.
As far as sketchbooks, the field is wide open ... I bet that, just like I do, most of you love to look for new good sketchbooks ... it's almost a sport. I am certainly always on the search ... and it's good to mix it up and try new papers. These nice Fabriano Artists Journals are my latest discovery ... though to tell you the truth after using them for a while I end up wishing the pages where all white.
Ok, that's it ... hope this helps a little. One note though, I made this page mostly to answer the curious that wants to know what materials I use, but it's by no mean what I recommend SketchCrawlers around the world to use. Just as I'd love to see drawings from different places, I also love to see different medias and materials used. SketchCrawl is about recording details around you by looking a little bit deeper and then drawing ... it doesn't matter what you use ! A ball point pen and some coffee will do just wonderfully, at least if you like coffee... as I mentioned my only suggestion is to pick tools that are light and easy to use.
Take care and good SketchCrawling !
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