Step 1
Create your document. Everytime we create something in Photoshop, like a call-to-action button, it is important to set big/medium size to our document even if the button is very small. The way we see the object during the creation is very important.
Step 2
The important thing here is not the background so let's skip that part and create our button directly. Create a new group and name it "button".
Step 3
With the new group highlighted, select the Rounded Rectangle Tool. Set the radius to around 3px and draw the button with white color.
Step 4
Duplicate the shape layer we've just created. Now, with the upper layer selected, click twice to open the blending options panel to apply a layerstyles to it.
Step 5
With the other layer selected, grab the Move tool by pressing V and move it down around 4px or 5px. Open up the the blending options panel and add the following layerstyles.
Step 6
To finish it let's just add text to it. I've used the Fontin font and its size to around 16px. Then, add a Drop Shadow layerstyle to it.
Final Result
