Reminder to create your custom Item Sets NOW
The Legacy Client will be unavailable in NA starting tomorrow and you will have to move to the new client if you haven't already. Since they won't be able to develop the Item Set creator for it until the transition is permanent, this means you won't have access to editing your sets outside of 3rd party options (or manually editing the config file) for a while.
If you've never used custom item sets before they can be pretty useful. If you frequently have to search for a specific item because it isn't on your Recommended list, having a custom list that includes all options for that champion or role is a much faster way of acquiring it, allowing you to shave a little time off of your shopping so you can get back to the fight ASAP. I personally recommend creating general lists for each role you play, so that whatever you take to there always has the items in the same spot and everything relevant is displayed up front without having to select sub-categories or type in a name.
#Edit: Important note that you must enter a match from the legacy client first to apply the item sets, so as soon as you make them start up a Custom Match before you leave.