The picture below shows you what I started with...two pieces of pine that I used to make simple chalkboards for Christmas decor.
First thing I did was cut away the sides and edges of the wood with a skillsaw. I just randomly cut away the wood. I then used a chisel to make deep grooves and gouges in the wood. Once I roughed up the wood, I sanded the entire piece with 100 grit sandpaper rounding and smoothing out the edges. I used the back of the wood which had been previously stained with a dark walnut Minwax stain so I removed most of the stain and took it down to bare wood. I simply used a primer paint mixed with plaster of paris and water and brushed the entire piece of wood with a whitewash. Once dry, which took minutes, I used the same method but using craft paint by Decoart called Khaki Tan. Again, once dry I sanded it with 180 grit sandpaper exposing some of the bare wood and whitewashed wood. I then applied espresso Minwax stain making sure to fill the deep grooves and gouges with the dark stain. The last step was to apply a clear Minwax paste wax, buffing to a smooth, glossy finish.
I liked the finished wood so much that I decided to hang a piece on each side of this mirror.