More information on Rally can be found on the Kennel Club Website at https://www.thekennelclub.org.uk/activities/rally/
Included in this information is a list of the exercises that may be included for each level of competition (this is a good guide on what to practise, although you will not know until you arrive at the competition which of these exercises have been chosen by the Judge to the included on the day); there are also bonus exercises that can gain you extra points. You will also be able to find shows listed here that include a Rally competition, together with entry details/forms etc.