Custom Taxonomy Sort allows you to explicitly control the sort order of all taxonomy terms.
Surprisingly, WordPress does not provide a mechanism for sorting taxonomies by a custom defined order. Taxonomies can only be sorted by name or id. Custom Taxonomy Sort allows the average user a mechanism to define and display terms in a specified order. After installing Custom Taxonomy Sort, each taxonomy term will have the ability to have a "tax-order" value associated with it. This order is specified by doing the following:
Custom Taxonomy Sort automatically applies the sort order to all instances in which the terms are displayed. All you need to do is define that order.
In addition to automatically sorting the terms, Custom Taxonomy Sort allows developers to override the automatic sort to offer finer control over how terms are displayed in different parts of WordPress. Manual mode can be started by changing "Automatic Sort" to "Off" in the Custom Taxonomy Sort Settings page (wp-admin/options-general.php?page=custom-taxonomy-sort-settings). Once "Automatic Sort" is switched to "Off", the terms will no longer be sorted automatically by the custom order. Instead, the custom sort order can be envoked with a new parameter for the "orderby" argument. Custom Taxonomy Sort allows you to use the following argument to access a custom sorted list of terms using "get_terms"
<?php get_terms('orderby=custom_sort'); ?>
Voila! Now, your terms will only be sorted by the specified order in the places that you want it sorted in this order. All other instances of displaying terms will revert to WordPress' default of sorting the terms by name. Additionally, you can specifically have the terms sort in ascending ('ASC'; default; e.g., 1, 2, 3) or descending ('DESC'; e.g., 3, 2, 1) order by adding the "order" argument.
<?php get_terms('orderby=custom_sort&order=ASC'); ?>
<?php get_terms('orderby=custom_sort&order=DESC'); ?>