How to turn a sketch into a color photo?

Step 1: Open the prepared photos with PhotoShop;

Step 2: Find "Image-Adjustment-Decolorization" (Ctrl+Shift+U) in the menu bar to turn the photo into black and white;

Step 3: Press "Ctrl+J" to copy the layer and add "Layer1"in the layer bar;

Step 4: Find "Image-Adjust-Reverse" (Ctrl+I) in the menu bar. Set the layer 1 as inversion; ?

Step 5: Select the overlay drop-down menu of layer 1 as "Color Fade", and the picture will become almost blank;

Step 6: Find "Filter-Other-Minimum" in the menu bar above. The radius is set to 1 pixel (adjust as needed, the value here is for reference only).

Last step: If you are not satisfied with the effect, you can double-click the layer 1 to bring up the layer style dialog box, split (hold down the Al key) the black slider of the next layer, and fuse the darkest pixel of the background layer into the final image. At the same time, you can modify the facial color with the deepening tool and the lightening tool to make the effect more natural.

Or directly select the adjustment parameters in the sketch under the filter menu. This effect is a bit rough.