Uniform - Which parts to wear? Cadet Orders of Dress

Often you will be told to wear a specific numbered order of dress: C1 or C4a for example.  But what does that mean?  

Each number refers to a specific way of wearing your uniform.  In some cases you will need to wear your tunic, dress shirt and tie, sometimes you will be asked to only wear your dress shirt and no tie.  Refer to these charts to make sure you are wearing the correct uniform.