(adsbygoogle = window.adsbygoogle || []).push({}); You will need:
A computer with Photoshop or some other image editing program.
A jailbroken iPhone/iPod/iPad with Winterboard installed.
A way to get your theme from your computer to your device (SSH, iExplorer, iFunbox, etc.)

Making The Icons:
First, select File – New in your image editing program.
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Name the image whatever icon you want to theme first (I’m doing the Messages icon). Change the width and the height to 1024, and click OK.
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Now just make your icon using all of the artistic technique you have! If you don’t know how to use Photoshop, look it up! There’s at least a million tutorials out there that can help you!

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I would recommend at this point to save the icon layered, so that you can make quick changes to it later (for photoshop just a .psd).

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Now click File – Image Size if your in Photoshop. For other image editing programs, find somewhere where you can change the size of the icon.

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Now, you need to resize the icon for the device that you’re theming for. Below is a table that shows all icon sizes for every device. For this tutorial however, I’ll only be theming the primary icon file for the iPhone 5.

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After you’ve done that, open File – Save As and save the resized icon as a .png from the pull-down bar.
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Making Folder Directories:
Now go to your desktop, or location on your computer that you’ll remember, and make a new folder naming it:

yourtheme.theme

Navigate into this folder and make a new folder called Bundles.

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Inside of that folder, make a folder, and name it the app’s Bundle ID. A Bundle ID is basically like a codename for an app, so Winterboard knows which icons to theme what. To find what the Bundle ID of a particular app is:

Navigate to /var/stash/xxxxx/Applications/ if it’s a stock icon and /var/mobile/Applications/ if it’s a third-party icon using your favorite file browser (i.e. iFile, Filza, etc.)
Open the Info.plist file, and scroll down to the key CFBundleIdentifier. The Bundle ID should look something like this:

com.company.appname

The folder you made previously now should look like this.
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Now, go to where you saved the .png of the icon you made in Photoshop and copy it over to this folder.

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Clock and newsstand icons are located in the folder:

com.apple.springboard

Renaming the files:

Now, you need to go back and do this whole tutorial over again for all of the apps you want to theme. A typical theme usually has somewhere between 100 and 300 icons. Once you do this, your Bundles folder should look like this:

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Now, all you need to do is transfer the .theme folder to this directory on your device:

/var/stash/xxxxx/Themes/

Now, all you need to do is apply your theme through Winterboard!

Credits:comp0ckerr (You must login or register to view this content.)