Founded in 2008, the artist-run design studio Fort Makers made a splash when it opened a showroom last fall on New York’s Lower East Side. Its inaugural exhibition featured sofas and chairs with upholstery that Fort Makers’ cofounder Naomi S. Clark covered in her characteristic motif: large, messy hand-painted shapes. (Most of them were blue, in homage to Yves Klein). Since then, every month or so, the studio devises a new installation. The current one, “Puffy,” is everything its name suggests: visitors are invited to explore, and reconfigure, a psychedelic playground filled with a forest of Clark-painted pillows.