Select Adjust>Add/Remove Noise>Add Noise. When the option window opens set the Noise to 100% and click Random Noise

Repeat this step once more (Adjust, Noise, Add ) with the same settings

Now choose Adjust>Blur>Gaussian Blur and set the Radius to 5.00.

Select Adjust>Brightness and Contrast>Threshold. When the Threshold window opens set the Threshold level to 197 and click OK.

Once again choose Adjust>Blur>Gaussian Blur and set the Radius to 5.00

Again select Adjust>Brightness and Contrast>Threshold. This time when the Threshold window opens, set the Threshold level to 210 and click OK.

We will call this image Water.

You should have the image shown below:

Leave everything as is and open a new image file with the same 385 x 477 pixels dimensions. Call this file Droplets. This time flood fill the new window with with a Gray-White gradients in PSP that you will create yourself. At the gradient fill pallette, select linear as shown below:

Then click the Edit button to open the new linear gradient dialog box.

Click New, then assign it the name rain. Click on the arrows circled in red below and choose gray and white colors.

Select 45 degree angle (shown above on the edit button example) then click OK to close the linear gradient dialog box. Remember to flood fill the canvas.

Now choose Selections>Select All, then Edit>Copy.

Move to the previous image (Water) and make it active by clicking its title bar. Select the Magic Wand tool and click in any part of the White background to select it.

Now choose Edit, Paste, Paste as New Layer to fill image with the gradient. You should now have the image shown below but your colors should be lighter:

Choose Selections>Invert

Effects>3D Effects>Outer Bevel and enter the settings shown below:

You should see the water droplets start to appear.

With the Water Image active and the selection still in place, chose Edit, Copy. Now move to the Droplets image which contains the gradient and make it active by clicking on its title bar. Then select Edit, Paste, Paste as New Layer to place the water droplets over the gradient.

Go to the Layers Palette and open it.
Click on Layer2. This should be the Waterdrops layer
Change the Blend mode of the Waterdrops layer to Hard Light and move the opacity slider to 50%. This will make the water look more realistic.

Save the image titled Droplets as a .psp file to keep the layers in tact. Now open an image you want to apply the droplets to. I used art.com to get the Singing in the Rain poster shown below:

Now open your Droplets file.Select the picture poster you are going to use and paste it onto the Droplets file as a new layer. Go to the layers palette and drag your picture layer below the water droplets layer. With the watch layer active, use the Move tool to position your picture in place beneath some water droplets

You can use the Eraser tool to remove droplets from areas where they are clumped together and not appear natural such as the rim of this watch. To do so, make the droplets laye the active layer and the erase away any unwanted water drops.
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Below is an example of a completed image: