How Do I Change the Opacity of a Drawing in Photoshop?

You can change the opacity of a drawing (or any layer) in Photoshop using the Layers panel.

Steps to Change Opacity:

Locate the Layers Panel: Ensure the Layers panel is visible. If not, go to Window > Layers in the Photoshop menu.
Select the Layer: In the Layers panel, select the layer containing the drawing whose opacity you want to adjust. This is crucial, as the opacity change will only affect the selected layer.
Adjust the Opacity: In the top right corner of the Layers panel (directly above the layer list), you'll find an "Opacity" dropdown or a slider next to it. Click and drag the slider to the left to decrease the opacity (making the drawing more transparent) or to the right to increase the opacity (making the drawing more opaque). Alternatively, you can click on the opacity percentage to enter a specific value. Opacity ranges from 0% (completely transparent) to 100% (completely opaque).

Key Considerations:

Fill vs. Opacity: Note that Photoshop also offers a "Fill" option in the Layers panel. Opacity affects the entire layer, including any layer styles applied to it. Fill only affects the pixels of the layer itself, not the layer styles. This can be important if you're using effects like drop shadows or strokes on your drawing layer and want to control how they are affected by transparency.
Layer Groups: If your drawing is part of a layer group, adjusting the group's opacity will affect all layers within the group. To adjust the opacity of only the drawing, make sure you select the drawing's layer itself, not the group it's in.
Blending Modes: Before adjusting opacity, it's worth considering blending modes (also found in the Layers panel). These modes interact differently with the layers beneath and can create different transparency effects than simply changing opacity.