Start with new document, fill background layer with solid color of your liking.
With very large soft brush (B), put some colored dots here and there.
Repeat until you are satisfied with the background. Apply some Gaussian Blur (in Filter menu - Blur) and add a little noise (Filter menu - Noise - Add noise).
... Or, you can use blue-to-black radial gradient to fill the background!
Set foreground color to white, set small (2px) hard brush, and draw the web. This is how it looks at 100% zoom...
... and this is zoomed out view.
Set web layer blend mode = Overlay, add some Noise to this layer, then go to Layer menu - layer style - blending options, and add some shadow (size = 1px, mode = overlay, opacity = 40-50%)
Now it is time to create water drops. Drawing drops one by one is not very efficient. Instead, we will use the power of Photoshop brush settings! Create new layer, then open Brushes palette window (from Window menu). Click brush tip shape. set Diameter to 13px (or adjust it accroding to your image size). Set spacing to about 200%.
Then click Shape Dynamics = make sure the checkbox is checked. Set Size Jitter to about 75%, and minimum diameter to about 50%.
Now make a single brush stroke, and you should get many nice "water drops" in a single stroke!
Do not stop until entire web is filled with water drops.
Our drops are now just white dots. To turn them into water, use the power of Layer Style! Open Layer Style, set layer blend mode to Multiply (dots are white, this will make them invisible) and add the following: - Drop shadow (multiply, 50%, 1-2px) - Inner shadow (angle = -90!, white color, Overlay, 2px) - Inner Glow (Overlay, 1px, 50%) - Bevel and Emboss (highlight mode = screen 40%, shadow mode = white, overlay, 50%, size=3px, soften=6px) - Satin (color = black, Overlay, opacity = 20%, distance = 8px, size = 2px). Much better!
Now, the lines of spiderweb are visible through water drops. This is not very beautiful. Right-click on "thumbnail" icon representing drops layer in Layers palette, context menu will open, click "Select Pixels".
Select layer with spider web, and delete selection.
I want to add small white highlight (as if reflecting light from above) to each waterdrop, but it cannot be done with layer effects. I also do not want to use brush to put every dot manually. Instead, Select Pixels of water drops layer again. Then go to Select menu - Modify - Contract (2px).
Create new layer, fill selection with white color.
Go to Select menu - Modify - Expand (2px). Then move selection 4 px down.
Delete selection. Then move selection 2px left, delete again, then move to the right, delete again.
Click to see final wallpaper!