For all the resources you might need , take a look at my Amazon Storefront for my top recommendations.
Modelling paste and stencils for texture in your art journal pages
You will see in the video how I have used modelling paste with stencils. I used a Matt Medium Heavy Texture Paste and built it up over masking tape and tissue, finishing off with acrylic paint.
You can get some great and very cheap art stencil masks over at Ali Express and they are all less than £2.50.
Tissue paper and embellishments for texture in your art work
Other methods for adding texture to art journals
Finally in the video I have used salt with watercolour, this really adds a grainy texture to your pages. You can also see more tips here including adding talc to thicken your acrylic paint.
Art Techniques for Art Journaling