Entering Hikawa shrine requires a purification ritual that begins with washing your hands, right then left, and rinsing your mouth (with your left hand). Next is the burning fire with smoke to waft over your head to burn off impurities and perhaps bring the blessings of Susanoo, the Shinto god of storms and seas. Now in your new state of purification, you can enter this Shinto shrine between wires covered with fluttering osame-fuda, the prayer paper strips pilgrims tie up at each shrine. White prayer papers are for novice pilgrims who aspire to progress to red papers and then to silver and gold as they become veteran pilgrims.
Inside the shrine, take a moment to toss a coin into the offering box or perhaps make a prayer or a wish to the god of the shrine. Sometimes photography is forbidden and other shrines forbid shoes so pay attention to signage. If you have an injury, buy some incense, light it in the shrine and waft the smoke toward your injury to get Susanoo's attention.
Almost every Shinto shrine in Japan (9,000 of them!) has a temple stamp and resident monks to hand paint the stamp into your temple book for a few yen. Purchase a temple book at any shrine and collect intricate stamps at all your temple stops. A full temple book is a gorgeous souvenir from Japan.
Should you be lucky enough to visit Japan in September, go to the Akasaka Hikawa Shrine festival.