How to make your own pouring medium?

How does the Liquitex Matte Pouring Medium work?

Here you can find a few tutorials related to acrylic painting mediums

The above photo is by Jan Huber. Here you can find a few tutorials on how to paint trees, with Ian Harris

Here you can find a few tutorials on how to paint trees, with Dranitsin

Here you can find a few tutorials on how to paint clouds, with Ian Harris