Gesso is important for getting your canvas or panel ready for printing. It can be bought from any art supply store, and it is used to seal and prime the surface before paint is applied. It also provides a good surface texture for accepting paint.
I mostly use bought canvas – which are already “gesso primed” – however I still will do a few layers of gesso in order to get the surface ready. When using hand built panels or canvas it is very important to make sure to prime it with gesso. I use the same method described below for both painting in acrylics and in oils.
Lay out your canvas or all the surfaces you are going to gesso. I always work in batches (when the space is available) for the best time management. Check and make sure the surfaces are clean and free from dirt and oils. If a canvas is dirty a wipe with a paper towel can clean it up. I often won’t open the wrapping on a bought canvas until I am about the gesso it. When doing this I also write what size canvas it is on the back, so I don’t have to measure later!
Select a large brush for applying gesso, be sure to check that it is not one that “sheds” as you won’t want to pick out brush hairs. Dip the brush into the gesso – sometimes I give it a little swirl – if the gesso has been used before, try not to get any dried gesso flakes into the gesso.
Apply the gesso to the surface in a thin even manner, make all your strokes go the same direction (horizontally or vertically). It is also a good idea to gesso the back of the canvas, to reduce movement of the canvas I don't always do this however.
Allow the first coat to dry, it should be dry to the touch and have no visible wet areas. Once you are completely sure the surface is dry, lightly sand the first coat with sandpaper. This smooths brush ridges and adds texture for adhesion.
After sanding apply a second layer of gesso in the opposite direction of the first layer. Sand it again and repeat the layering a few times. (I usually do 2-3 layers).
Once completely dry your canvas should now be ready to paint! It’s a good idea to give the canvas a wipe with water (acrylics) or mineral spirits (oils) before you start painting.