Step 1:
Let's start out by creating a new file. I used a 400x200 pixels canvas set at 72dpi, and I filled my background with a white color. Now create a new layer set and name it 'Date Icon'.
Select the Rounded Rectangle Tool and above your screen under the options palette choose Fill Pixels, set the radius to 8 px and check anti-aliased. Create a new layer and draw a rounded rectangle with 56x66 px dimensions and #E5E5E5 color shade. On the bottom right corner of your rounded rectangle draw a rectangle so the corner is straight.
Step 2:
Under Layer Style(Layer > Layer Style) add a Drop Shadow, Inner Shadow, Satin and Gradient Overlay blending options to your gray rounded rectangle layer.
Step 3:
In a new layer draw a black rounded rectangle with 49x55 px dimensions.
Step 4:
Under Layer Style(Layer > Layer Style) add an Inner Shadow, Inner Glow and Gradient Overlay blending options to your black rounded rectangle layer. Then set the layers blending mode to Lighten.
Step 5:
Now choose the Horizontal Type Tool and set the font family to Verdana, bold, 12 pt, none and black color. In a new text layer type the month on the top side of the icon.
Step 6:
In a new text layer add the day using font Arial, bold, 18 pt, none and white for color.
Results:
Date Icon:












More Photoshop: