My favourite watercolor paints to use are Daniel Smith watercolor paints, because of their high quality pigment and granulating effects in select paints. I also find that almost all their paints dry well in the pan and re-wet well.
I also use Windsor and Newton Professional Series Watercolor Paints, specifically their Quinacridone Gold.
For beginner watercolor artists, don't get worked up about the paint you use! I started out by buying one tube of each of the primary colors: Red, Yellow and Blue.
I use Arches 140-lb cold-pressed Watercolor paper almost exclusively. It's my personal favourite!
For several of my tutorials, I also use Canon XL series, which is a much more affordable paper.
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