You don't have to remember all the code. The wiki is pretty comprehensive.
http://www.eqemulator.net/wiki/wikka...=QuestTutorial Another good resource is pre-existing code. There are several events already written that cast spells on regular intervals and reset on a wipe. You can check out PEQ's quests for examples.
If you are trying to use the client as a target, you need to remember that the client does not trigger the timer event, so it won't be automatically available to that sub.