I'm a nineteen year old Chinese Canadian person and I came to Canada when I was twelve. My accent became almost invisible when I was around fourteen years old because I would just watched TV all day long after schooltill I go to bed at night. However, when I went to an all Chinese international school in Canada, I developed a more heavy Chinese accent because all of my friends had a little bit of Chinese accent. What's interesting is that I didn't notice my new accent until I graduated from high school and got into college in the States. Now my non-Chinese American friends think I have a heavy accent whereas my Chinese American friends think I have little accent. Isn't that weird? I don't care how many people think accents are cool, there are always more people who hate accents. For example, in classes people look at me differently when I comment on a particular passage. In the first month in one of my English classes I didn't participate in class discussion at all except occasional small phrases so the prof didn't know I wasn't born here. During this time, I consistently got A's and check-plus on all of my written papers. However, after I started speaking up and people found out about my accent, she started giving me B's and A-'s even though I doubled my efforts. I don't care what you people say, you cannot possibly understand the descriminations we go through as people with foreign accents. So stop telling us that we should be proud of them or whatever, just try to understand us first ok?
But anyway, after realizing the accent problem, here is what I am doing right now to reduce my accent. When I was twelve my father bought a special machine callsed Bu Bu Gao BK-919 which is pretty much a cassette recorder with unique language learning functions. It is very convenient as it is designed for accent reduction. The listener plays a passage on the cassette, presses a button to record his own imitation of that passage and then presses it again to hear the original passage followed by his own recording. That way, he knows which exactly where his accent is wrong. There are three speed intervals which allows the listener to slow down his recording or the passage itself so that mistakes can be found at a more microscopic level. It is fantastic and it works even better if you use it every night before you go to sleep! I used to do this when I was twelve and I listened to recordings of Disney fairy tales and repeated after them. Nowdays though I can't find any cassette recordings in the closest library to me so that is a little bit of a problem. I've tried the whole voice-over thing for movies and it doesn't work as nicely as the machine because you tend to have a distorted version what you sound like until you hear the recordings.
Last week my aunt mailed me the newest machine produced by the same brand. Because I can't get my hands on any good cassette recordings, I am planning to buy blank cassetts and record the dialogues I hear on my favorite TV shows and then playback and record my own imitations on the machines. I'm hoping this will work although it'll depend on the quality of the recordings. One more note, I think people can make their accent go away entirely because I've seen people who came here the same age I did and don't have a single trace of an accent left. On the other hand, I've also seen people who came here even earlier than me who have more fobby accents than mine. So the possibilities are endless. But in the end, it depends on 1)how hard you try, and 2) the method you are using.
Good luck and I hope this helped!