The show jumping judge will assess your control and presentation to the fences, your position over the fences, and how you ride the course, scoring each fence and also overall collectives for how the course/jumps were ridden. 
 
Jump courses are the same set course which changes each month, choose whichever height you're comfortable with.
 
You can make the course up in a mix of cross poles, and straight bars and they can be set at any height with fillers or no fillers however if an oxer is shown on the course plan this must be added (again any height).  Any tack is allowed in the jumping section.