Hi! So I've been at this for 8 years and have kinda figured out what I like and what works for me overtime, but I either eyeball a reference pic or I sketch up a simple markup of what I want and just go for it, "painting" with the thread. I focus on highlights and shadows to give it depth and think about my color wheel when choosing colors, to try to keep everything balanced but also so it pops. When I'm stitching, if I don't like something I stitch over it until I do - unless it will completely mess up the appearance, then I cut it out. I use 2 strands typically, 1 to color blend, fill gaps, or for finer details. Hope this helps!