This is how you add color to your sidebar:
1) Sign in to your CafePress account and your account page will show up.
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2) Find the shop you want to edit and click "manage."
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This takes you to the "Shop Management" page:
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3) Click on "Customize Shop Appearance." This brings you to the "Customize Your Shop" page:
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4) Click on "Colors & Fonts." This will bring you to the "Colors and Fonts" page:
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5) Scroll down to the bottom of the "Colors and Fonts" page:
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6) You'll see the "Sidebar Background" area. Here is where you can either choose a named color from the dropdown menu, or type in your own hex color (the six digit letter/number combination).
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Here is my So Much Life T-shirt store, if you'd like to see how my sidebar color looks there. This store is a modified blank Cafepres template and the sidebar color was altered the same way as the example above.
For tips on choosing HTML colors and a website color scheme for your CafePress shop, you may want to check out my post on choosing good colors for your website by using free color tools.