Decreasing the cost of one's painting surface allows for more experimentation. To make the surface less costly, you can purchase a large piece of hardboard or masonite at your local hardware or home improvement store ( a full size piece is 4 feet x 8 feet). Full size will require a truck to transport it home. You could have it delivered or most stores will at least cut the full size board down to size to fit in your car. Some stores will custom cut the pieces for you. In calculating the sizes of the painting boards, the loss of approximately 1/4 " for the saw blade needs to be considered for each cut.
Recently David Gray (link) and (teaching/information link) posted his method to prepare his hardboard panels on instagram. I added a PVA size (link) step to my preparation after reading this post. David Gray uses cradled baltic birch (from Trekell) as his support. Here is his prep from that post: "I forgot to mention that prior to step one I typically will "size" the panel with something. I usually use one coat of shellac but there are other fancier and maybe better products such as a PVA size. ------ My rather involved (sorta) process of how I prime my panels. This panel from Trekell is a beautiful 1.75" cradled Baltic Birch 12x12 inch. I first just brush on acrylic "gesso" with an ordinary house painters brush. Second, I spray a bit of water on the surface. Third, I brush it out smooth with a haki brush. The water helps to brush the primer out smooth and decreases raking marks from the brush. Let dry and lightly sand with 400 grit sand paper. I repeat these steps 3 or 4 times brushing in a different direction each time. The resulting surface does have some very subtle lines from the brush, but they are only noticeable in extreme raking light. I love this surface for my small works".
I use a soft, inexpensive brush to coat my boards with gesso and make sure that I wash the brush immediately in water to be able to use it again. I have tested several brands of gesso and am pretty convinced that I can't tell a great deal of difference in them. I am not great at sanding and I don't find it help me smooth my surface very much. Therefore, I have recently experimented with spreading the gesso on the board with a small bowl scraper (link). I am finding that to achieve a smooth surface, I need some practice with this tool. However, already it is superior to the brush marks I get with my inexpensive brush application. It is also way better for clean up.
Recently, I found Gamblin Ground (link). I will experiment with this and discuss it in a later post. It is beautifully smooth to touch. However, it takes a week to dry, unlike the 30 minutes or so for gesso.to be ready to use.