At CfC (Conference for Creators) 2 which took place in Zaragoza, Spain, in 2020, I gave a presentation titled Designing precrease patterns for clean folding of tessellations and boxes. It describes my approach to designing models which have a clean look, i.e. have as few unnecessary creases on visible parts of paper, as is practical to achieve. While designing and folding tessellations this way requries more work than just folding a complete grid first, I think the extra effort is often worth it since the models look much better. Finding an origami construction which leaves no traces behind is also an interesting challenge.
You can view the complete slides here: Designing precrease patterns for clean folding of tessellations and boxes. I later also wrote a blog post about pre-creasing which adds some more information.
Note: after the presentation, someone (Anna Kastlunger, I think), pointed out to me that the abbreviation PCP was already taken (Progressive Crease Pattern). This is something I missed, so now I think it would be better to introduce another abbreviation for Pre-Crease Pattern, for example PreCP.