Adjustment Layers
The Adjustment Layer pop-up menu at the bottom of the Layers palette (it’s the half black and half white circle) allows you to apply adjustments that will affect multiple layers. This is the most versatile method for applying adjustments and it is such a powerful feature that I’ve devoted an entire chapter to it (Chapter 11 “Adjustment Layers”).
Fill Layers
The options in the Layer > New Fill Layer menu allow you to add solid color, gradient, and pattern content to a layer. This is especially useful when combined with Vector Mask, as described in Chapter 15, “Collage.” If you don’t want a fill layer to fill your entire document, then make a selection before creating one, which will create a layer mask. After a fill layer has been created, you can reset your foreground and background colors to black/white by pressing D. Then you can use the Eraser tool to hide the area and the Paintbrush tool to make areas visible again.
Solid Color Layer
Choosing Layer > New Fill Layer > Solid Color will bring up a dialog box that asks you to name the layer you’re creating. Once you click OK, it will open the color picker, where you can specify the color that will be used for the solid color layer. After you’ve created one of these layers, you can double-click the leftmost thumbnail of the layer in the Layers palette to edit the color.
Gradient Layer
Choosing Layer > New Fill Layer > Gradient will bring up a dialog box that asks you to name the layer; this will create a new layer that contains a gradient. The gradient is always editable by double-clicking the leftmost thumbnail in the Layers palette. If the Align with Layer check box is turned on, then the start and end points of the gradient are determined by the contents of the layer instead of the document’s overall size.