Photoshop's Custom Shapes palette contains a number of
very useful objects. You can increase the usefulness of many
of them by combining two or more shapes. And you can save these
shapes for future use.
STEP 1
Open a new document in Photoshop. This image is 400x400 pixels,
but you can work with any size. (And since we're working
with vectors, you can design small, knowing that the shapes
will resize perfectly and without loss of quality to any size
at all.) In this example, we'll convert a 10-point star
shape to a 40-point sunburst.
STEP 2
Select the Custom Shape tool in the Toolbox. In the Options Bar,
open the Custom Shapes palette by clicking on the triangle
to the right of the sample shape. In the upper-right corner
of the palette, click on the triangle to open the palette's
menu.

STEP 3
At the bottom of the menu are a number of sets of custom shapes,
installed by default with Photoshop. For this example, let's
load Shapes. In the box that opens, click Append to add the
shapes to the palette rather than replacing the default set.
STEP 4
In the Custom Shapes palette, select 10-Popint Star by double
clicking on it. In the Options Bar, we want to set the tool
to create “work paths” rather than shape layers
or pixel-filled regions.
STEP 5
So that we can get exact alignment when adding symbols, press
Command-R (Mac) or Control-R (Windows) to show the Rulers.
Now right-click or, for Mac users who have a one-button mouse,
Control-click on the Ruler and select Percent from the pop-up
menu. (Indeed, not only can you set the Rulers to Percent,
Mac users with a two-button mouse can right-click to open contextual
menus. Cool, eh?)
STEP 6
Position the cursor at the 50%/50% mark - the exact center of
the image. Hold down the Shift and Option keys (Mac) or the
Shift and Alt keys (Windows). Drag toward one of the corners
of the image. The Shift key will maintain the width-to-height
ratio of the shape to the original (“constrain proportions”).
The Option/Alt key enables you to drag from the center. If
you'd like, you can drag vertical and horizontal guides
from the Rulers to the 50/50 mark to make it easier to identify.
Using the menu command View> Snap To> Guides (selected
by default) makes it a breeze to be accurate.
STEP 7
Use the menu command Edit> Transform Path> Rotate. In the
Options Bar, enter 45 for the angle of rotation. Hit the Return
or Enter key to accept the value in the filed, then hit the key
again to accept the transformation.
STEP 8
In the Options Bar, make sure that the Custom Shape tool is set
to add to the existing work path (see the insert in the following
Image). Again from the center of the image, drag another star,
this time of a slightly different size.
STEP 9
Rotate the path another 45 degrees and add a third star, at a
different length. Repeat the rotation and add a fourth star
to the path. The path is complete.
STEP 10
Use the menu command Edit> Define Custom Shape to create the
custom shape, which will be added to the Custom Shape palette.
Here are some additional simple shape combinations, using only
those shapes available to you in Photoshop 7.
NOTE: Remember that your custom shapes aren't really safely
saved until you save them in a set. You can do that through the
Custom Shapes palette or through Edit> Preset Manager. In
the dialog box, switch to Custom Shapes in the pop-up menu. Shift-click
on your new shapes to select them and from the Preset Manager
menu, choose Save Set.
TIP: Don't save your third-party and custom shapes, styles,
Actions, brushes, etc. inside the Photoshop folder. Should you
ever need to (gasp!) re-install Photoshop, having a separate
folder (or folders) keeps them safe.