Tax is a simple add-on for the ACF (Advanced Custom Fields) WP plugin that lets you set the taxonomies of a post in a custom metabox.
Tax add-on generates elegant lists of check-boxes that can be formated in a number of user selected columns to save space.
Move the acf-tax.php file in your theme folder. To activate just add
register_field('Tax_field’, dirname(__File__) . '/acf-tax.php');
in your functions file and you're ready to go.