Pronunciation of "I'm going to"

I'm not a native English speaker but I've recently moved to the US. I've been noticing that when people say "I'm going to" (or I'm gonna), a lot of people here always pronounce it like "I muh-nuh", so apparently this is a normal thing to say where I live, but I had never heard it before.

How common is it? Is that how you're actually supposed to pronounce it, and as a non-native speaker, do you think it's a good idea to learn to use it and talk that way, or I shouldn't imitate this at all?

Thank you in advance.

Solution 1:

As a native speaker of standard Midwestern American English, "I muhnuh" sounds perfectly ordinary, to me, hearing it from another American English speaker. However, if I knew you were not a native speaker of English, there might be a problem. Since it's very unusual for a non-native speaker to have a native-like command of casual conversation, I might not understand you, or, especially if you didn't say it right, I might think you were making fun of my own pronunciation. The right way to say it is something like [ɑjmə̃ɾ̃ə̃], with reduced vowels (not "uh") and with the n flapped.