Beth makes some good points, but I see you asked for quickest, not quick. (1) Focus: Know what you want it for. (to be cool?, to communicate? to pass as a native?) . I was first interested in the characters, So I learned a little & did calligraphy courses. Then I wanted to holiday, so I wanted oral. Spoken Chinese from podcasts worked well for me. Lots of practice listening & speaking. . (2) Find encouraging things: Chat online, QQ, Qtalk, watch movies (with subtitles), whatever gets you a buzz of improving. Join classes. QTalk has some excellent classes. (3) pay for it: I've met some really good tutors. I got distracted & never built much vocab. Keeping up a regular programme, book course, or tutor will give you on track for building vocab. Chinese for travel is not so difficult: (a) Chinese are mostly friendly & many will be happy to help you, just for the chance to chat. (b) Many Chinese people are incredibly tolerant of accent. They have so many dialects, that they hear. Mess up the sounds & sometimes tones & they will likely work it out with you. . As Beth says, tones are important. What I did was I put Chinese conversation & podcasts in the car. Every time I went places, I listened. After a while I stopped hearing English syllables & started hearing Chinese sounds with tones. Songs don't have cl;ear tones: not as good. . Hope it helps.

"There is no royal road to geometry." ~ by Euclid

Well, I know a way in which you can learn to SPEAK the language in 10 ten days. It is a language learning system called Pimsleur, named after the language scientist who made it. I know this seems a bit unbelieveable {I haven't tried it myself}, so let me explain. Pimsleur constantly studied the language learning center of the brain, and the his principle is this: a baby doesn't learn a language by studying flashcards and what not. No, a baby learns a language by hearing it used by the people around him/her. The baby does this even though its brain isn't fully developed. Applying this principle to someone whose brain is more developed, that person can learn the language in a shorter amount of time than the baby {ten days}. If you get Pimsleur, you'll basically listen to the language you want to learn for a certain period of time, every day, for ten days. Needless to say, the Pimsleur language leaning system will not be able to teach you the written form of the language，and you'll still have to memorize a good chunk of characters and their pinyin counterparts in order to write, but at least your work will be cut in half.

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