List of fixed character descriptions (eg. 白勺的)
The characters with same or similar pronunciation are usually distinguished by making a word from them, like


  我叫柳星雨，雨是下雨的雨，不是宇宙的宇


The only common one I recall is the following where sometimes people are trying to distinguish between two surnames both pronounced as zhang


  弓长张 and 立早章