Most get to Kanas Lake from Urumqi, more often than not as part of a group tour. The tour option is generally easier and cheaper than doing it on your own, running between around RMB 600-1000 for a park pass, transportation, hotel accommodation in Bu'erjin and inside the Nature Reserve, along with transportation to various scenic spots within the park. However, you'll be bound to the group's itinerary, more or less, so for those who favor freedom of movement, you can bus up from Urumqi, then take a bus or taxi from Bu'erjan to Kanas. Note that, depending on the time of year, it can be a bit tricky to find transportation when you want it, and a bit expensive when you do (a taxi from Bu'erjin should run about RMB 250 or so once the haggling's done).