I too used to love experimenting with different colours and mediums. Which types went well together. Pastels and water colours together look very pretty but to me always seems to need something else to give it impact. Unless of course it is a picture of softness and light - like mist over the water.
I was trying to show my granddaughters a few tips on water colours and how to do a 'wash'. They were very intrigued and put great effort into it. Somehow the jar of water got tipped over and ran across some of their paintings - 'now we have a real wash, grandma' they were quick to point out!
