With the selection still active, select the Gradient Tool and select a linear gradient (B) in the options bar at the top.

If everything is ok, then we should see a preview of the gradient in the options bar (A).

Make sure that it goes from black (left) to white (right). If that's not the case then make sure that the option reverse is not selected (C). If you don't see a black & white gradient, then double click on the gradient in the options bar (A) and select the gradient from the list and click OK.

We are now going to draw a gradient from left to right. We start at the red dot and pull the gradient all the way to the blue dot.

After you're done, deselect the selection by pressing Ctrl + D (command + D on the Mac) on your keyboard or by selecting in the menu Select / Deselect.

Set the blending mode of the layer in the layers palette to Overlay.

 

 

 

Add a Layer Style by clicking on the layer style icon in the layers palette

First select Drop Shadow and use the following settings:

Now select Inner Shadow and use the following settings;

The result of this later style should look like this:

 

Remember; you're always free to make slight changes to the settings in my example. It all depends on what your background looks like or how big your water drop is.

Press de letter X on your keyboard to switch the fore- and background; the foreground color is now white. Now select a hard brush with a size of 6 pixels (the size depends on size of the water drop) and click once in the upper left corner of our water drop.

That's it. A quick and simple way to create a convincing looking water drop.

It's recommended to create a Layer Set (Click here for our Layer sets/groups Photoshop tutorial ) for both water drop and highlight. That makes it easier to move the water drop by just moving the layer set using the Move Tool .
You can add extra copies of this Layer Set by dragging and dropping the Layer Set on the New Layer icon .

Remember, it's also easy to resize the content of a Layer Set by selecting the Move Tool and selecting in the menu Edit/Free Transform or by pressing Ctrl + T (command + T on the MAC).
Pulling a corner with the mouse will allow you to resize the content of the layer set. Make sure to hold down the shift key while you do that to constrain the proportions of the water drop.

When you resize a water drop, make sure you change the distance of the drop shadow; make it smaller if the water drop is going to be smaller, make it bigger if you want a larger water drop.

You can change the shape of the water drop by selecting the layer with the water drop and using the Liquify Tool ( In the menu choose Filter/Liquify... ) and using the Forward Warp Tool

If you want to distort the background then you have to Ctrl + click ( Command + click on the MAC) on the thumbnail of the layer with the water drop and it will create a selection based on the water drop. You then have to make the background active (it has to be unlocked, if it isn't double click on it to unlock it) and with the selection active you go to the menu and select Filter/Liquify... and use the Bloat Tool Be aware though; this means that you can't move the water drop anymore, since moving the water drop does not move this magnified area of the background.

Have fun!