Find an old black-and-white photograph with one or more person in it. You can use one of your family photos if you want to.

The photo should be a good quality scan.

Open it in PhotoShop.

Duplicate the background layer. You are going to do adjustments and coloring to the copied layer.

Keep the original image (layer) in case you need it.

Remove all colors:

Image > Adjustments > Desaturate

Adjust the levels if your image is not contrasted enough, or too dark / light.

Image > Adjustment > Levels

Add a layer. Name in COLOR.

Change blending mode to "color".

Use a soft brush (hardness 0).

In Brush's Options - set Opacity between 10 and 50%

Pick a skin color.

Apply to the face, hands, etc.

Set Eraser tool to hardness 80 - 100% to remove paint.

Save colors as swatches - so you can fix, adjust, restore the painted areas.

You can give your swatches names.

Continue painting the rest of the image.

You can use multiple layers for coloring.

Try different Blending modes - in addition to COLOR - it can be OVERLAY or others.

After you are done - it's time to place "before" and "after" images next to each other.

Go to the Menu bar:

Image > Canvas Size

1. Double the Width

2. Move the anchor to the left (as shown).

Use Move tool.

Convert Background layer (original photo) to Layer 0.

Move the original photo to the right.

Add a signature.

Print.