Dive into each vocal and consonant sounds in the target language, try to reproduce them by yourself, record you, hear you, (repeat). A professional can help you and also offer you a series of recordings and pronunciation exercises that will help you to really improve your accent. In my opinion, accents are part of out identity but it shouldn't be a communication obstacle when interacting with others.

There are some good videos on Youtube, for example: https://www.youtube.com/watch?v=USKrBTvgY_s

Something which has really helped me recently in trying to mimic a South African accent, and which no-one ever talks about, is noticing how "close" the vowel sounds are. This also has an effect on the consonants. In phonetics, "close", roughly speaking, refers to how close your tongue is to the roof of your mouth when you speak. A South African (I have discovered!) keeps his tongue closer to the roof of his mouth than I do, as an Englishman. Realising that has suddenly made it much easier for me to make the sounds I want. Try speaking with different degrees of "closeness" and see if it helps you get what you want. Just to give my opinion, by the way, I think an Indian accent is normally very nice, and totally valid as a variety of English...

You need to listen a lot (movies,music ...) And paractice with ur self