Masaya is known as the center of Nicaraguan Arts and Crafts, the most popular of the markets is the Mercado Viejo located right in the center of town. Nearby Masaya are located is the Masaya Vocano National Park which has walking trails and a visitor center, combine your visit to the park with a tour of El Coyotepe, a fort built in the 1890's amd later a Somozan Prison. The old fort offers an incredible view of the volcanoes, lagoons and lakes of this region.
Upon your arrival in Nicaragua, you will either arrive at the International Airport, which is located on the "Carretera del Norte" across from The "Best Western" Hotel or if traveling overland from either Costa Rica from the south or El Salvador/Guatemala/Honduras from the north arrive at one of the International Bus Terminals such as "Nica" or "Tica" Bus. Managua is a large sprawling place with no centro or "downtown" (destroyed by Earthquake in 1972 and never rebuilt) and it is not recommended to take take crowded city buses carrying luggage and valuables, Taxis are everywhere and very reasonable from 10 Cordobas (70 Cents US) per person up depending on length of journey.
Masaya is only about 25 Km. or 17 Miles south of Managua, Express Buses (1 hour or less) leave from the Terminal near La UCA University every 30 minutes during the day.
Avoid the "professional tour operators" in Managua and the "real estate salesmen" in Granada and have a nice stay in one of the nicest countries on earth..Nicaragua!