Summarize this article:

For Brazil in 2014, the last minute sales process begins on April 15, 2014. You can also go to a FIFA ticketing center to purchase these tickets.  During this phase, you will know immediately if you will receive tickets to the match. Your payment will be processed immediately. These centers are available in host cities. The tickets can be purchased via debit card or cash.  As of June 1, this is the only way to purchase remaining tickets to the World Cup. There are no restrictions based on previous game purchases. All tickets are subject to availability.  Find information for specific World Cup ticketing centers at this address: http://www.fifa.com/worldcup/organisation/ticketing/ticket-information/ticket-collection/index.html

Summary:
Sign into your FIFA account in the last phase. Select tickets for the categories and matches of your choice. Purchase your tickets in real-time. Opt to purchase tickets at a World Cup ticketing center as of June 1st.