ContactBeforeInsert Class

public class ContactBeforeInsert {
    public static void setContactTitle(List<Contact> cons){
        for(Contact c : cons){
            c.Title = 'Admin';
        }        
    }
    
}

ContactBeforeTrigger

Trigger ContactBeforeTrigger on Contact (before insert) {
    ContactBeforeInsert.setContactTitle(trigger.new);
    /* Moved the logic to ContactBeforeInsert class
     * for(Contact c : Trigger.new){
        c.Title = 'Admin';
    }
  */
}