Basic set up for colorizing a drawing in Photoshop.

Scan

Put drawing face down in scanner.

Open Photoshop.
File/import hpscanjet 5590 TWAIN, or whatever name matches the name of the scanner.
Scan your drawing.

Save as a PSD file on the desktop.
Drag to your USB
Take back to your computer using a USB or mail.

Adjust the drawing

Open in Photsohop.
Go Image/Mode and make sure it is RGB
Alt-double click the background layer to unlock.

Drawing is probably too light.
Adjust levels: Image/Adjustments/levels or Ctrl L.
Move black point to the right into the flat area in the histogram.

Drawing layer

Go to layers palette. F7 if you don’t see it.
Change blend mode of your drawing layer from Normal to Multiply.
This will allow you to “see though” your drawing.

Name the layer drawing.
Lock the layer using the lock icon.

Sky background layer

Add a new layer by clicking on the little post it icon at the bottom of layer palette.
Activate that layer so it appears blue. Drag it to the bottom.

Click on the foreground color and select a sky blue.
Ctrl-backspace to fill it with the background color.
You can also use Edit/Fill foreground color.

Name that layer sky.
Lock that layer using the lock icon in the layers palette.

Ground layer

Use the marquee selection tool to select the ground area.
Make the foreground color a green.
With the selection tool active, right click, fill with the foreground color.

Start your first house coloring layer

Make a new layer. Make sure it is in between the 2 layers. This is where you will start coloring. Name it house base.

Making selections and coloring

Use the Polygonal lasso tool in the toolbar on the left to make selections. The polygonal lasso tool is accessed underneath the lasso tool. You need to press down on the small arrow at the tool to access it.

Make selections, being sure to “close” them. Fill them with colors using Alt backspace or right click fill.

Adjust your colors using HSL: Image/Adjustment/Hue Saturation or Ctrl U. Slide as needed.

Make as many layers as you need.