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Should I buy Mod Podge?
What paper should I use for Art Journaling?
I am a bit hit and miss when it comes to paper. I started out journaling in a Moleskine Cahier insert for a Travelers Notebook (Midori style tn), this paper seems fine for thicker paint such as acrylic, but is not very good for watercolour as the paper wrinkles. Watercolour paper is the best for any watercolour work (or canvas) and mixed media paper or sketch pad paper for acrylics, or again an art canvas.
You can make your own inserts for tn's using a mix of paper. All these papers can bought cheaply from The Works or Hobbycraft and even the Poundshop for sketch paper. Mrs Brimbles has an excellent tutorial here Making Mixed Media Inserts for Travelers Notebooks.
What other art equipment should I buy?