The easy answer is - go sailing! A more complete answer offers several possibilities.
The Summer Sailstice site is designed to show you what others are doing or have done so you have a menu of ideas or can add your own. If you visit the 2015 Events Page you'll see races, cruises, open houses and numerous events and individual sailing plans. You'll find sailors who were crossing the Atlantic as part of the Clipper Round the World Race and organizations like Orange Coast College or Saratoga Lake Sailing Club who are hosting open houses.
How do I decide what to post?
The 'Sailing/Event' page gives you options.
The Sailing/Event pages gives a map of what everyone is doing for this year's Summer Sailstice. They come in three 'flavors':
Public Events: the yellow pins are for events open to the general public - boat or no boat. You're invited to show up and participate in whatever event activities are described on the event page. This might include sailboat rides, sailing festival or a sailing facility open house. For example the Califorina Inclusive Sailing Event in Newport Beach, CA.
Demo Events: These events are designed to showcase the wide variety of sailing options open to sailors: races, cruises, rallies, raft-ups, ocean crossing, lake sailing, etc. They are for current sailors participating in any of the organized events to help showcase all that sailing has to offer. For example the Windjammers Summer Sailstice Race in Bayville, NJ.
Individual Plans: the blue pins are for everyone who plans to sail to post their indivudal plans to sail on their own or as part of an organized event to show the world who, what, where and how people are celebrating sailing around the world. For example, the Mia and Andy will be sailing aboard 'Isborn' as part of World Cruising's Delmarva Rally around the Delmarva peninsula between the Chesapeake and the Atlantic ocean.