Typical Indoor painting supply list:

D’ARCHES WATERCOLOR PAPER, 140 lb,  It MUST be Arches paper.  If you have any problem with this, let me know.  2 half sheets + some quarter sheets.  Bright White

Board that is bigger than your paper. Do not stretch, tape or staple your paper to the board.
1″ clear-handled Taklon flat brush — such as  Winsor Newton 995
#10 pointed round brush —white sable series 785 or Connoisseur series 367

LIDDED PALETTE — such as Aqua Pro, or John Pike, or Steve Quiller’s with

  artist grade  watercolor paint  such as Daniel Smith, Winsor Newton, Da Vinci, Holbein. Have at least 3 primary and 3 secondary hues.

Feel free to come with your own palette.

Be sure to have the basic 6 hues (red, orange, yellow, green, blue, violet)
If you are squeezing out more paint I suggest arranging your paints in a color wheel (ie rainbow).
I use Daniel Smith colors.
(cobalt green )
pthalo green, or Winsor green
(cobalt teal, cerulean blue)
pthalo blue, or Winsor blue
ultramarine blue
mypalettecobalt blue                 quinacridone purple (new)
(quinacridone violet)
quinacridone red or perylene red
quinacridone rose
cadmium red medium
quinacridone burnt orange (or sienna)
perinone orange
quinacridone gold
cadmium yellow light, or Winsor yellow
green gold
+ any of your favorites

Update: I have added Quinacridone purple and taken out viridian; cobalt green is for sedimentary glazing.

All of the colors that are sedimentary are marked on the photo.  The rest are dyes or “stains” – no sediment.

a sketchbook
#2 or 2B pencils
white eraser
2 pint or quart sized water containers
a roll of tissue (tp); also paper towels