Why have a sketchbook or art journal?

At first, I just didn't get why you would have an art journal or sketchbook.  I thought what a waste of time, why not create directly onto your paper or canvas etc.  Then........ I did a sketchbook course and that completely changed my thinking.  
I now have a few sketchbooks on the go, some I made during my Creative Circle program earlier this year.  I also ahve a couple of sketchbooks in different orientations and spiral bound and hard bound. These books have been invaluable to me and my artwork. 
I use them for experimentation of colours, mark making, new supplies and ideas.  If I happen to do a course, I use a sketchbook to document my learnings.  If an idea comes to me, I put it into my sketch book. One of my favourite things to do in creating art is to colour mix so I use it to swatch colours and experiment with different palettes. 
Recently, I was working on a piece and knew it needed something, there was a little something that was missing.  I flicked through a couple of sketchbooks and voila, there was my answer with one of my mark making experiments.  It is just what was needed to bring the piece to life.   
Of course, when you are out and about a small sketchbook, a couple of pencils and even a small watercolour set is a great way to capture a moment in time. 

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