Dear Ashish,
Here are few practical tips to improve your English.
1. Buy two dictionaries - one good English to English and another, English to Hindi or your own mother tongue.(with pronunciation help)
2. Buy thick address diary with seperate identified pages for each alphabet.
2. Subscribe a English newspaper and start reading the news items of your interest area - Politics, sports, movies, gossip, business.
3. Underline the new, unknown words. Check the meaning and pronunciation of these words. Note down these words in your address dairy in the respectitive alphabet pages. To start with, stop when you note down 10 words in a day.
4. Next day, before you pick up the newspaper, pick your address diary and try to recollect the words, their spellings and meanings. Read it if you do not remember it. Then start looking for another 10 new words from the newspaper for the day. Repeat this every day. Your collection will be increasing by 10 words everyday. You may not be able to remember so many words but no problem. Read them, spend few moments with each word.
5. Now start relating to the words reappearing in newspaper which were already noted and learned. Now see their usage in the sentence. Start trying to use these words in your sentence.
6. Pick up English text books of CBSE for primary classes and start learning simple grammar - noun, pronoun, verb and adjectives.
7. Start speaking English no matter how wrong. Just remember, no body is perfect. You are better than others as you are making conscious effort of learning. To start with, speak wrong English with confidence. Slowly, you will start realising your own mistakes and auto correction will follow. Believe me.
8. Thank people who point out your mistakes. Do reconfirm the pointed mistake from your grammar and dictionary.
You can do it! Just do it !!
With best wishes,
MM Banga