Visiting Shichifukujin (The Seven Deities of Good Fortune) is an event where you visit shrines that enshrine Shichifukujin to pray for your good fortune between January 1st and 7th. Shichifukujin is said to derive from the Chinese subject of Chikurin Shichiken (seven Sages in a Bamboo Grove) or from the famous Buddhist term from the sutra Ninnougyou, shichinan sokumetsu shichinan sokushou (seven adversities disappeared and seven fortunes arose). The group comprises Bishamonten (god of worriors), Daikokuten (god of wealth, commerce, and trade), Benzaiten (goddess pf knowledge, art, beauty), Jurojin (god of long life), Fukurokuju (god of popularity), Ebisu (prosperity), Hotei (god of abundance). You can actually worship them all in Shinjuku.
※As for the details of each Buddhist temple and Shinto shrine, please see link than the above.
※Red seal charges, mount, Seven Deities of Good Luck sacred image are charged.
※"Shinjuku Yamanote Shichifukujin Tour" goes in each Buddhist temple and Shinto shrine. Please contact each Buddhist temple and Shinto shrine for the details such as acquisition methods of mount.