It's been quite some time since the time I said I'll share my technique (to some people). So this post is on this topic. I'll share my secrets to you, okay?
Material :
Any suitable surface to doodle
Permanent Marker (I personally love Faber Castell Multimark permanent marker)
Acrylic paint or fabric dye (for base coloring - give you a smooth surface to doodle)
Clear spray (just in case water spilled on your artwork!)
Ps - You don't have to create outlines using pencil first then do the inking. You can just doodle using the permanent pen. No worries. Practices make perfectto~*