Step-by-step: Painting magical runes
First I paint the book pages without any runes. I use the Flat fan high bristle count default Photoshop brush in various shades of brown to give the pages a weathered and aged look. I pay special attention to the edges of the pages, making them crinkled and torn.
On a new layer, I use a default hard Round brush to draw some runes in a solid, light yellow colour. These symbols are my own design. For this technique (and just in general) it’s helpful to keep your layers well- organised, so I name this layer “rune layer”.
I duplicate the rune layer and name it “glow layer”. Using the Hue/Saturation window, I change the glow layer to a medium gold colour. Then I use the Gaussian Blur filter to soften and create the glowing effect, adjusting the Blur and Layer Opacity to enhance the look.