I teach wet on wet watercolor a method I have worked in for over 30 years. That means I take 140lb. cold press paper and wet it front and back with a natural sponge until it is wet to the core. I don’t stretch it – pin it down or tape. The surface tension of the water with the paper and smooth surface underneath (either gator board or another slick surface) holds the paper flat. If it is not flat – if it has bubbles or begins to warp I wet it till it will lay flat.
I smooth the paper down like I am putting up wallpaper. I use a natural sponge (not cellulose) and I work with the paper at an angle so the water can flow downhill. Once it is flat I use the sponge again. I wring out the sponge and wipe down the paper. Any space that I have planned to leave white I dry with a paper towel.
I have fresh paint on my palette. I use a limited palette with 3 shades of blue, two of yellow, one of red and burnt sienna. All greens, purples and grays are mixed. The reason to mix is because as watercolor dries the component colors separate just a little creating a bit of push and pull.
Watercolor dries 1/3 lighter than it appears when wet. That means you have to really plan and think about your darks. Don’t be afraid of using pigment. To have paint on the paper when it is dry you have to put paint down while it is wet. If you are not using fresh pigment or paint and trying to reconstitute dry paint from your palette you won’t get much pigment – what you will get amounts to a wash and it will be very light when it dries.
Once you destroy your white on a painting – it is gone. You cannot get it back. The cotton paper stains. You can lift it off and lighten it but it will never be as white as it was. That is why you plan. You have a preliminary drawing or plan to paint from. You plan every bit of your painting. That does not mean you might decide to change it if the painting tells you you need to – but that is the subject for another time. Leave more white than you are comfortable with to start with – you can always destroy it. You cannot get it back.
Wet on wet painting forces you to work fast, use a large brush, think in terms of shapes and large areas. All the more reason it is necessary to plan. The saying I have heard is “plan like a tortoise, paint like a hare.”
If you are interested in a workshop check here for future listings.