You just need a function to add Custom Taxonomies to Custom Post Types. In previous article we made WordPress default taxonomies called Category & Tag to support our CPTs. Here we are going to create custom taxonomies for them.
Tag » Taxonomy
Add Default WordPress Categories and Tags to Custom Post Types
You can add default WordPress Categories and Tags taxonomies to Custom Post Types through passing taxonomies parameters to arguments. In previous article we had learnt how to create CPT using code in functions.php. Here I will explain how can you use WordPress default built-in taxonomies like Categories and Tags with those CPT.