I have been design a couple theme of wordpress. A large of number of my theme full with customization. For the example, If you download “Magazine Evolution” theme, you have to arrange the code such as category ID.
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Point your cursor to one of your category at your Manage Category administrator and see of the bottom your screen at status bar. You will find the category ID then put them in the code.
Manage Category ID under index.php : in the CAT SECTION TOP LEFT/RIGHT, CAT SECTION MIDDLE LEFT/RIGHT,CAT SECTION BOTTOM LEFT/RIGHT you will find this code :
……$display_categories = array(1->THIS IS CATEGORY ID-CHANGE THIS VALUE);……..
and you will customize another files to customize ID categories. Let me know if you need question.