Step 2: Right click on your shape tool and choose Rounded Rectangle Tool

 set the radius (on the top toolbar) about 5 pixels

Step 3: Change your foreground and background to light green and dark green with these values

 Step 4: Now draw a small rectangle on your document. On the Layers tab, double click on your new created layer to open the Layer Style dialog box. Use these effects:

    + Drop shadow:

    + Gradient Overlay:

(choose Foreground to Background option) 

    + Stroke:

After using these effects, our rectangle will look like this:

We will draw something on our rectangle.

Step 5: Right click on the shape tool again, but this time we choose Custom Shape Tool

Step 6: On the top toolbar, you will see a small arrow on the right side of the "Shape" word, click on it. If you just see a few shapes then click on the small arrow on the top right of the box, choose All to load all shapes

 Select a shape you like and draw it on your rectangle

My note is pink just because it is the selected layer. In fact, your shape will be green because it uses your foreground color by default.

 Step 7: To change your shape's color, double click on its layer to open the Layer Style dialog box, use Stroke effect with yellow like this:

 Use the Horizontal Type Tool(T) to write something you want. Here is the result:

You can stop here! But if you want to make your button more attractive, I will show you an interesting technique.

 Step 8: In the Layers tab, choose the top layer (by default, maybe it is Shape 2 layer or your text layer, if you used one) and click on "Create a new layer" icon

Step 9: Right click on the Marquee Tool(M) and choose Elliptical Marquee Tool

 draw a small ellipse on the top of your rectangle

Step 10: Press Shift-F5 to open the Fill dialog box, select White in the drop-down list. Click OK

 Step 11: Double click on your current layer. In the General Blending, reduce Opacity to 25. Deselect all other effects if they are in use.

 Now press Ctrl-D to deselect the ellipse, here is the final result

Note: if you don't use a white background, you will see an unwanted white area outside your rectangle. To fix this problem, you have to make a precise selection (which is intersected by your rectangular selection and your elliptical selection).

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