- Using the brush tool, make a small rain-drop. (Click somewhere on your image, once).
- Go to Layer - Layer Style - Blending Options, apply the following settings and press ok:

- Go to Layer - Layer Style - Drop Shadow, apply the following settings and press ok:

- Go to Layer - Layer Style - Inner Shadow, apply the following settings and press ok:

- Go to Layer - Layer Style - Inner Glow, apply the following settings and press ok:

- Go to Layer - Layer Style - Bevel and Emboss, apply the following settings and press ok:

- Now use the brush tool to make more drops, or make any shape you want too. You can also apply the same effect on a text to make rain-drop text :).

- Final result should look something like this: