Practice listening to a lot of English, whether it is video, TV, movies, youtube or Native English Speakers and start mimicking what they say. Grab your phone, record yourself and listen to it to see how you pronounce the words. Can you understand clearly what you are saying? A great site to use is readlistenlearn.net as they have stories and articles in different levels and you can read and listen to them. You can hear how the reader is pronouncing words and you can then try to say the words like them. Many of my students use these methods to improve their pronunciation.