Check out this article from the incomparable Jacob Cass of Just Creative Design:

How to make your next website design pop!

Web design is one of those areas that, when done right, you just know it. The finished site looks refined and well done—it pops! There are a number of ways that you can achieve this by polishing off your design in Photoshop. Here we look at some of the ways to do just that.

1 [LAY OUT THE FUNDAMENTALS]
Before you go about making your website pop, you must first have your fundamentals in place. By this stage you should have done the research, laid out your website appropriately, and done most of the basic design work—but you haven’t applied the polish. In the following example, we’re going to look at some techniques used for a chocolate delivery website; however, these same techniques can be applied to any website.

2 [CHECK ALIGNMENT AND SPACING]
Alignment and spacing in website design creates order, organizes the page, and groups parts of the website for easy navigation. In the screenshot above you can see the guidelines in place ensuring everything is aligned (the grid is from www.960.gs). Notice how the logo and all of the text is left aligned? Also take note of the even spacing around the boxes and text. Use guides in Photoshop to ensure all of your elements are aligned. To add a guide to your document, drag it from one of your rulers (press Command-R [PC: Ctrl-R] to turn rulers on).

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