Prepare before you start the trail. The route is approximately 25 miles and most treks are scheduled over four days. You will need to have a reasonable level of fitness although extensive walking experience is not required. Pack a pair of walking boots and waterproof clothing. Try and acclimatize to the altitude in Cuzco for a few days before you begin walking if you have arrived from lower ground.
Learn a little about Inca culture before you begin the trail. The city of Cuzco has museums and guided tours that give a good introduction to Inca history. Learn about the route and you will have a better appreciation of the ruins you will see at places like Sayacmara and Winay Wayna. Away from the Inca trail itself, take a walk to the ruins at Choquequira if you have a chance. Also read up on the wildlife that you might see. The trail includes an array of fauna including wild orchids, you will see llamas grazing on the hills and you might even see a condor if you are lucky.
Book a guided trek with companies that have expertise in the region. Inka Trail expeditions run a 4-day hike where you will camp for three nights. On day four you have a one hour trek to the entrance of Machu Picchu to see the site at sunrise. You will then have a 3-hour tour around the historical ruins with an expert guide talking about the history and archaeology of the Inca's lost city. Prices include meals, porter service on the trek, entrance to the trail and return rail fare to Cuzco.
Travel responsibly. The Inca Trail is a UNESCO World Heritage Site but large numbers of visitors have damaged the trail and continue to harm the environment. Make sure that you travel in an approved party and camp in designated sites. If you hike the trail with Responsible Travel you will be helping the local economy as local staff are employed and paid a fair wage. Staff are also provided with trekking shoes and tented accommodation on the route.
Find an itinerary that allows you plenty of time at Machu Picchu. After trekking for days you will want to spend time enjoying the views and exploring the ruins. Sunrise and sunset at the site are both memorable experiences. Pay a visit to the local town Aquas Calientes and have an hour in the thermal baths if you have time. Set in a gap in the cloud forest, the baths are a spectacular place to relax after a few days trekking.