NA LCS Finals Tickets?

Can anyone explain to me how I can actually buy tickets now that the 'pre-sale' is over? I'm a first-timer in terms of trying to see LCS live and just now figured out now that I can make it scheduling wise. So how do I actually get a ticket? Are there likely to be enough tickets by the 23rd? I read this article way back when but was confused by it and assumed tickets would just be on sale starting July 2nd through whenever they sold out.