Hello! So… Here is how I do, I hope that will be helpful :)
1. Before you go in the game, you need to find celeb’s images that you want to create. A front view picture and a side view picture, it better be horizontal viewing, and then I would say “observation images" is important!
2. Second, you need to find anything cc that you will be using. For me, the first decision is the skin, according to the image and choose a most closely skintone. (If you can’t find anything cc matches…..just do It yourself XDDDD)
3. In CAS, I will start in facial contours ——> nose ——-> eyebrows ————> eyes ———-> mouth (No rules, just according to personal habits.)
4. When you’re finished, that sim probably not closer your celeb, so now we need some correction method. Taking a front view screenshot of your sim.
5. Now open your sim screenshot and celeb image in the photoshop. Overlapping them and adjust them to be the same size. You can adjust opacity to see what facial features you need to re-tweak.
P.S. Created a celebrity sim must be patience, you’d better prepare yourself. That’s it, good luck! XD