How can I get rid of my accent?
This can be a complicated issue, involving different stages:
1) Identifying isolated sounds — the vowels and consonants — and learning how to make them so they sound American (or British).
2) Learning to get the emphasis on the correct syllable of each word.
3) Learning the overall music of the way people speak — where they typically raise and lower pitch, vary rhythm and so on.
You can listen to good speakers with these things in mind, ask a trusted friend to coach you in return for something you can do for them, find an ESL teacher to help you, go to a good acting coach who specializes in dialects, or work with a speech therapist who works on accent correction.