Sacred valley started at 15 miles north-east of Cusco, and continue towards north-west for another 35 miles. A number of Inca ruins, series of picturesque villages along with cliffs and valleys make Sacred valley a not to miss tourist spot, whoever visiting Cusco.
People usually visit Pisac, Urubamba, Puka Pukara and Ollantaytambo in Sacred valley. Only Ollantaytambo is little far from Cusco, all other places are within one hour journey form Cusco.
Usually people visit Pisac, Urubamba valley, Ollantaytambo and Chinchero as a Sacred valley tour. You may find packages where you will be offered to stay in Urubamba valley and after visiting Pisac and Ollantaytambo. Next day you will go to Chinchero and finally to Cusco. Tambomachay (the Inca Fountains), Puca Pucara (the Red Fortress), the amphitheater of Kenko and the Sacsahuaman Fortress are also visited, but they are very close from Cusco, so they are visited as part of Cusco tour.
You don't have to arrange tours to Sacred valley until you reach Cusco. There are plenty of operators around Plaza de Armas at Cusco whom you can arrange at once to tour the Sacred Valley places. Depending on the time available and how much you want to spend, you can select a touring operators. Usually tour operators will charge you around $ 20.00 for a daylong tour which include Pisac, Urubamba and Chinchero with a English speaking guide.
Tuesday, Thursday or Sunday are the market day in the Sacred valley towns hence you can visit those days, if you can. Sacred valley town are located at lower altitude than Cusco. So those who are effected with the altitude problem may stay at any of the Valley towns ( Pisac, Urubamba or Ollantaytambo). Even you may start with staying at Machu Picchu, then Ollantaytambo, then Pisac and finally at Cusco, since Cusco is at the highest elevation. So your body will get the proper acclimatization.
There are suitable hotels at Pisac, Urubamba and Chinchero, so staying there is not a problem. But if you don't want to spend much time you can always take a one day tour package from Cusco and visit all this towns.