Start Practicing the following:
Daily read english newspaper atleast for one hour. by reading, i mean, read it loudly enough not to irritate people around you. However you should hear your voice. Initially read it slowly just to get control over pronunciation. Also, dont bother for the meaning of the words. After one week or so starting understanding meaning of the words, sentences. you may take help of dictionary. also, you can note down difficult words with meaning and pronounciation. Try to use these words in your day to day life.
Start english conversation with friends, family members, colleagues. Avoid using same words again and again.
Hope this will help you to start speaking english.
Initially i had same problem. Everyday more than hour i used to speak besides mirror. my friends and family members are teased me like anything.
Now am speaking to my client(US) also. so don't care about others. English just a language any on can speak easily.
Always write correct English. Mind your spelling, capital letters etc. Learn at least 05 to 10 new English words from Oxford English dictionary daily. Write them in a vocabulary book and revise as many times as possible until it registered in your mind. Read a lot without concerning the full meaning of the text. This will help you familiarize the language.
The real effective approach to improve SPOKEN ENGLISH is the following.
1. Practice FREE SPEECH every day and if possible record your voice and later find out the flaws you have made and later correct them by verifying,this way you will keep eliminating your errors
2. Observe and watch DIRECT SPEECH of native speakers....not newspapers and news but INTERVIEWS AND INTERACTIVE SHOWS.This way you can learn correct PHRASES,DICTION AND PRONUNCIATION as well.Reading newspapers can improve rapid reading,voice modulation and knowledge but there you run the risk of pronouncing as per your pronunciation,just as the way we learned our mother tongue by observing,listening and responding and not reading.Reading is a tool to be used later to enrich an already grammatically correct speaker.
3.start THINKING IN ENGLISH as your FIRST LANGUAGE INFLUENCE problem will be aborted and you will construct sentences first in mind and then speak hence less errors.
4. ABOVE ALL....HAVE PATIENCE & PRACTICE WITH PEOPLE as it is a gradual but dynamic process.
I have incorporated these techniques with my participants who are from vernacular medium and have reaped results dramatically.
Hope it turns the same for you,Wishing you kindle the flame of knowledge and good speech.
I am an English trainer. I fully agree with Priyen that reading anything interesting aloud is the best way to learn any language. After a week's reading you must start a process of identifying and underlining the helping verbs like "is, are, am, was, were, will, will be, would, should". These are the basic necessities in sentence formations. Then comes subject word agreement which is equally important. You have lots of comphrehension lessons in google too. try them later. Good luck.