Add a Bevel and Emboss layer style by double clicking next to the layer title in the Layer tab (or Layer>Layer Style>Bevel and Emboss).
With the bevel style set to inner with smooth technique, set the depth to 1000%, the size to 50 (will depend on you text size, change to suit your image) and no soften, 0%.
Adjust the shading by unchecking Use Global Light, then set the angle and altitude to 120 and 30 respectively, you can adjust this later to suit your needs. Change the Gloss Contour to the bumpy pattern. Change the highlight mode to normal at 100% opacity and the shadow mode to lighten at 90% opacity. Be sure to set the color of the highlight and shadow modes to white; this shouldn't be overlooked because its what makes this effect work.