Step 6: Continue Selecting All Areas And Copying Them To New Layers

Continue making selections around each of the areas that you're going to want to colorize separately and copying each area onto its own layer until you're done. Make sure you click back on the "threshold" layer each time after you've made a selection, and then use the same keyboard shortcut, Ctrl+Alt+J (Win) / Command+Option+J (Mac) to copy the selection to its own layer. Also, make sure you give the new layer a descriptive name.

I've gone ahead and made selections around each area of the girl I'm going to want to colorize and I've copied each area onto its own layer in the Layers palette:

Step 7: Colorize Your First Section With A Solid Color Fill Layer

With each of the sections we want to colorize selected and copied onto their own layer, the hard part is done. We're now at the fun and easy part - colorizing each section. To do that, we're going to give each section its own solid color fill layer. I'm going to start at the very top of my Layers palette with the girl's hair.

First, I'm going to click on her "hair" layer in the Layers palette to select it. Then, I'm going to hold down my Alt (Win) / Option (Mac) key and click on the New Fill Or Adjustment Layer icon at the bottom of the Layers palette:

Then, while still holding Alt/Option, select Solid Color from the top of the list:

Holding down the Alt/Option key tells windows to bring up the New Layer icon for us before adding the solid color layer. Give your solid color layer a descriptive name. Since mine is going to be used to colorize the girl's hair, I'm going to name mine "hair color".

Also, make sure you select the Use Previous Layer To Create Clipping Mask option this time:

If you don't select it, your solid color will cover the entire image, which isn't what we want. Choosing this option will make sure the color only fills the area inside the selection, which in my case here is the girl's hair.

Click OK, and Photoshop's Color Picker appears. Again, choose any color you want because you can go back and change it any time. I'm going to choose orange for her hair, and then click OK.

I can now see my orange solid color fill layer above the "hair" layer in the Layers palette. It's indented to the right and has a small down-pointing arrow on the left to indicate that it's being "clipped" by the layer below it, preventing it from covering the entire image area:

Here's what the girl's hair currently looks like: