Supply list:

Plenty of paper, pre cut in sizes like 10”x10” , 12”x12”, 9”x11” You can us a good quality pad or cut yourself from full sheets.
Look for heavy papers 140 lb is a nice weight.
This about the surface you like to work on. Hot Press or Cold Press
Hot will give you a smooth surface without texture.
Cold will give you some texture.

Suggested papers:
Reeves BFK white Hot Press 140 lb or 300 lb
Arches Aquarella Hot Press 140 lb or 300 lb
These papers come in full sheets so they must be cut to desired size.
Pre- cut water color pads are convenient and come in a variety of workable sizes. 
Suggested pads:
Cason water color pads. 
Arches Watercolour- Acuarela comes in both 140 lb & 300lb
Blick art supplies has many to choose from.

Drawing material: 
Caran d'Ache Neocolor Artists' Crayons
Colored pencils 
Drewent water soluble graphite pencils. 
Pastels 

Brushes:
Water color/ acrylic soft synthetic.
Wide variety of sizes. 
If your looking for BIG  checking out Liquitex Free Style brushes.

Paint:
Acrylic paints bring a full pallet of color including white and black

Mediums:
Golden Acrylic Glazing Liquid comes in both Gloss and Satin 

Other supplies:
Freezer wrap or pallet paper
Low tack tape, drafting tape or blue painters tape
Pallet knife 
Tools for scrapping 
Paper towels
Bring along your own photos or drawings to work from.
Small items you have collected from nature. 
Spray bottle filled with water for misting.