Step 1

Start with your shape on a new layer. Try experimenting with a shape
of your own.

I drew this with the polygon lasso tool an filled it with green.

Step 2

Make a selection around your object. Ctrl/Cmd+Click on the layer Thumbnail.

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Step 3

select>modify>contract.

I chose 10 pixels

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Step 4

Your selection is now contracted.

Step 5

Now to make the groove.

Select>modify>Border
I chose 5 pixels

Step 6

You should see the double selection now.

Step 7

Press the delete/backspace key to erase the object on the selection.

Deselect

Step 8

Now to add the bevel:

Add the layer styles (press the little f on the bottom of the layers
palette.)

Choose the inner bevel option

*Optional: add a drop shadow too.

Step 9

And the shape is now bevelled!

If you want you can add some text, select it, switch to the object layer
and hit del/backspace to chisel out some text.