I found this very helpful.

This video is worth watching if you wish to add mixed media to your illustrations and paintings. I haven’t done this type of work before but the video gave me a lot of ideas of how to add depth to my work. I am excited to try it as an addition to my own techniques. I will post the outcomes soon for feedback – thank you to Gabrielle in the video she identifies her site and where you can find more resources.

Also thank you to Kimberly L Revels for posting it in the first place.