This tutorial produces sweet looking metallic stars through the use of careful placement of gradients. Easily reproducible for a text effect as well. Created with Adobe Illustrator CS6. Let's get started.
1. Draw a star
Starting off with a basic fill and no stroke, draw out a star using the Star tool. Hold down the Shift key as you drag to keep the star's angles in check.
2. Create segments
Enable Smart Guides (View > Smart Guides). With the Line Segment tool, hover over an anchor point until you see an "anchor" label appear. Click (and keep the mouse button held down) and drag to an opposite point until you see the "anchor" label and then release.
It's critical the path you draw makes the anchor to anchor connection. I've colored the 5 paths to illustrate what points should be connected together.
3. Dividing paths
Open the Pathfinder panel (Window > Pathfinder). Select the star and all of the lines and click the Divide command on the panel. The result is 10 separate shapes. Ungroup (Object > Ungroup) the shapes so you can work with them individually.
Decide on what colors you want in your star at this stage. I'm going for a metallic gold look so the gradients I use will reflect that. And, to save some time, I'm going to start off with pre-made metallic gradients included in Illustrator. Go to Window > Swatch Libraries > Gradients > Metals to open the swatches.
5. Editing gradients
Open the Gradients panel and click on the first metallic gradient labelled "Gold". The gradient will appear in the Gradients panel.
To keep things simple, I'm going to remove all but 2 color stops. I'm going to work with the light gradient first so I eliminated the 3 color stops on the right and moved the stops to ends of the gradient bar.
6. Applying the light gradients
At this point, I'm going to drag the sample swatch box off of the Gradients panel and onto the following star segments.
7. Make adjustments
Use the Gradient tool to make angle and color flow adjustments to the applied gradients.
8. Applying the dark gradients
Deselect any selected shapes and click the Gold swatch from the Metals swatch panel to edit the gradient in the Gradient panel. I'm eliminating the following color stops to create the dark gradient.
Adjust the color stops to the ends of the gradient bar.
Click and drag onto the remaining star segments. Make adjustments to the gradients as needed.
9. Offset the segments
Select all of the segments and, from the menu bar, go to Object > Path > Offset Path. Enter the following values and click OK.
10. Reverse the gradients.
Select an individual offset (or inset in this instance) and click the Reverse Gradient command on the Gradient panel. Repeat for the remaining segments. And that is that! You're done!