Administratively, Yunnan is divided into 16 prefectures. Some of those are autonomous prefectures for various ethnic groups. For the traveller, Yunnan can be divided into seven regions:
Kunming Prefecture is without a doubt the heart of Yunnan Province. You will likely pass through here whether or not you want to in Yunnan (not that it is a bad thing!).
Central Yunnan is west of Kunming and where the hills start becoming more rugged. This is a very popular region for backpackers. It includes Dali Prefecture and Chuxiong Prefecture.
Eastern Yunnan is filled with the gorgeous scenery of the rolling hills of neighboring Guizhou and Guangxi transforming into the high, hilly plateau of Yunnan. This area includes many tourist sites not regularly visited by backpackers. It includes Zhaotong Prefecture, Qujing Prefecture and Wenshan Prefecture.
Southeastern Yunnan is amazingly diverse, in one day you could pass through arid badlands, lush pine forests, barren hills and tropical rainforests. The urban centres in this area of Yunnan are very compact and it is quite easy to get around from city to city to see the sights. It includes Yuxi Prefecture and Honghe Hani and Yi Autonomous Prefecture.
Southern Yunnan is geographically and ethnically part of Southeast Asia, but politically part of China. Jungle covers most of the terrain and this is probably the best region of China to escape the winter. It includes Simao Prefecture and Xishuangbanna, a major tourist area.
Western Yunnan is home to some very rugged, off-the-beaten-path terrain. Once the location of the famed Burma Road, it is now one of China's most alluring destinations. It includes Lincang Prefecture, Baoshan Prefecture, Dehong Prefecture and Nujiang Prefecture.
Northwestern Yunnan is a chunk of ancient Tibet within Yunnan's boundaries. Many traveller's come here to experience Tibet without having to enter the actual province. You will find towering mountain ranges and fascinating culture here. It includes Lijiang Prefecture and Diqing Prefecture.
Shiping - the culture of the YI people, Shi Ping(石屏,shi ping)
Its name literally means south of the clouds. The province is one of the most diverse in China. The Northwest of the province is heavily influenced by Tibet, with whom it shares a border. The South is influenced by its proximity to Laos and Myanmar. The province is famed for its multitude of ethnic groups, whose diverse customs can still be seen today. Of China's fifty-five officially recognized ethnic minorities, twenty-five can be found in Yunnan: about one-third of the population is not ethnic Han-Chinese.
The official language of Yunnan is Mandarin Chinese (or Putonghua as it is known). The region is home to a plethora of dialects from Chinese, Tibetan and Thai language families. Yunnan is home to many minority groups who each have their own different language.
Local towns will often have their own version of Mandarin which are sub-dialects of the South-Western dialect of Mandarin common to Yunnan, Guizhou and Sichuan. Despite a heavy accent, the local dialect of Chinese is very similar to Northern Mandarin with only minor regional differences in grammar and pronunciation.
Until 2005, Kunming was accessible by rail from Hanoi, Vietnam via a narrow-gauge railroad built by the French. The Chinese section of this rail route is now closed, though, so the best way to get down to the border is by bus to Hekou (from where you can cross the border to Lao Cai and take the train to Hanoi), or by air from Kunming directly to Hanoi.
There is a railway from Hanoi to Nanning, Guangxi, and one with some sensational scenery from Nanning to Kunming. Another rail route reaches Kunming from central China via Guiyang, Guizhou, and a third one comes South to Kunming from Chengdu, Sichuan. All of these train routes offer spectacular scenery, with long stretches of bridges and tunnels.
Wujiaba Airport in Kunming is the biggest airport in Yunnan which is very near the urban, the taxi fare is about 10-15 Rmb if you want to go to any place of Kunming from the airport.
Kunming has non-stop service from Beijing, Xiamen and other Chinese cities. There are also flights to Southeast Asia. Laotian airlines and the consulate are both in the Camellia hotel, Kunming.
Bus, by thumb
There is a road from Laos into Yunnan. It's not too hard to hitchhike, but it will take some time because of the often abyssmal road conditions and inept drivers.
Golden Peacock Shipping company runs a speedboat three times a week on the Mekong river between Jinghong in southern Yunnan and Chiang Saen (Thailand). Passengers are not required to have visas for Laos or Myanmar, although the greater part of the trip is on the river bordering these countries.
From Kunming you can take a train to Dali, but from there you'll need to travel by bus north to Lijiang and Shangrila. see Yunnan tourist trail for details.
Bicycle touring in Yunnan is a very good way to explore the local landscape and many cyclists from world have done this.The Dian-Zang highway(Yunnan Tibet highway) is one of the best cycling routes in China, and many cyclists gather together to explore the landscape and ethnic minority culture. You can hire bicycles in some cities, like Lijiang and Dali. It is possible to delivery your bike by train or bus. Yunnan Cycling  a local cycling website.
The Caves of the Liujng (Wenshan region)
The Stone Forest (Kunming region)
Hike the Mekong (Lancang) River
Soak in the hot spring waters at Anning - 34 km from Kunming
For the game of Go (Chinese: weiqi 围棋), the best Chinese stones are Yúnzǐ (云子), Yunnan stones. They are quite different from Japanese stones, and much cheaper. The flower and bird market in Kunming is a good place to pick up a set, and it is possible to visit the factory near Kunming. See the Yunzi article  on the go players' wiki, Sensei's Library.
Guo Qiao Mi Xian, meaning "Crossing the Bridge" Noodles, is a local style of steamy noodles with a variety of vegetables and meats. The price of Guo Qiao Mi Xian is from Rmb 3 to 15, but normally you cannot feel the difference except the price.
Yunnan people eat lots of spicy food, nearly each dish you order in the restaurant is very spicy, so if you don't like spicy food, you should tell the waiter or waitress first, in Mandarin: wo bu chi la, which means I don't eat spicy food or wo bu xi huan la cai, which means I don't like spicy food.
The tofu in Shi Ping county /石屏/ is very famous. The sauerkraut in Xinping county is famous. Xinping is a Yi Nationality Autonomous County in Yuxi city.
Rupin, Yunnan goat cheese, is the only cheese traditionally produced in China. Its quite soft and doesn't taste as strong as European one.
Yak butter tea
Yunnan red wines. Some, such as Shangrila brand, are quite good.
Beer Lao, imported from Laos. Local brands, the usual Chinese brands, and other imports are also available, but Beer Lao is very popular with travellers.