How can I improve my vocabulary, spoken English and...

Hello Amit, from your questions, I understand that you have the mind for English and a positive attitude to improve your proficiency in English Language. Also, it is evident from out of your questions that you are conscious about what you speak. Unless you are not so, it wouldn't have been possible from your end to put your questions marking areas you wish to improve upon. You deserve appreciation for doing a right self-analysis on your need. Let me help you understand what fluency is all about and its relation to one or all of the following symptoms: Nervousness, Speechlessness (lacking the faculty of speech, temporarily unable to speak, running out of words), Fear of failure.
 What is Fluency?
Fluency is uninterrupted flow of words with the correct word order (word sequence) in way it makes the right sense or throws a clear message which is easy to understand by a receiver or a group of audience.
What is Vocabulary?
Vocabulary is a set of familiar words specific to the context or subject of talk (Context-sensitive means "depending on context" or "depending on circumstances" or "depending on the subject of talk". It may refer to Context-sensitive meaning, where meaning depends on context or the subject itself). Acquiring an extensive vocabulary is one of the largest challenges in learning a second language. But one could have a reserve of words specific to the context or conditions or situations they engage themselves with.
Example:
List of words associated or context to Travelling
1. Booking a Holiday (book, depart, arrive, reservation, destination and so on...)
2. Packing (suitcase, backpack, currency, appropriate clothing and so on.
3. Travelling to your destination (check-in, departure gate, airport terminal and so on.
4. Arriving at your destination (landing, customs, baggage collection point and so on.
5. Activities (places to visit, describing places, asking for help and so on.
6. Places to Visit (amusement park, museum, art gallery, and so on.
7. Describing Places (vibrant, lively, modern, historic and so on.
8. Asking for Help (How can I get to the help? Do you know where the help is?) To be a successful speaker, you must focus on your vocabulary and improve on upon the fluency in the English language, follow the sequence listed below:
1. Plan your subject of talk well in advance.
2. Understand the purpose of your talk and the audience.
3. Do research about the subject of talk.
4. Define the sequence of talk
5. Remember the key words associated with each topic.
6. Practice to perfectness prior to speech.
7. Start to complete with a positive attitude.
Find yourself a mentor.

Hi Amit,

Whatever, I could collect from your question is that you hesitate to talk being uncertain how people would react on the way you speak. For you, I think there is just a little need to boost your confidence that will inculcate automatically when a little basics of grammar are taught to you and someone works on your communication skills. You can also listen to English new channels, movies, read the newpaper and also find a firend with whom you may converse in English without hesitation.

Think in English. Sometimes the ambitious  thing about talking in a new language isn't the language feel, but how you think about it.

i. Talk/discourse to yourself.

ii. Use a mirror.

iii. Focus on bent, not grammar.

iv. Try some voice, twisters.

v. Listen and repetition.

vi. Pay mind to stressed sounds.

vii. Sing along to English songs.

Hello Amit,

Firstly and foremost I would recommend to overcome from your hesitation is to stop bothering about grammar mistakes and speak whether you are speakng correct or incorrect. Now questions comes that would others notice,yes but not as much as you think they would. Just focus more on your content and the message you want to convey and gradually you will gain confidence with your fluency and spoken english with little practice from English dictionary, English newpapers etc.

All you need to do is to just speak which is more important rather then being conscious and not speaking at all.Because its practise which gains you confidence and perfection.

Practise english speaking daly with a friend partner, colleague or a trainer everyday.

Hi Amit,

You can read good novels and even the supplementary in newspaper which is quite interesting. You can read interviews that appear in papers and magazines so that you know about conversations.

Inorder to get relieved of stage fear, you must first be confident of your speech. Make your speech interesting with anecdotes and incidents filled with humour. When you see people smiling or laughing at your jokes, you also are relieved from stress.

Secondly, if you find it difficult to have eye contact with the audience, then you may look at the rear wall or the ceiling so that you may not see the expression s of the audience.

Finally, practice your speech as many. Times as possible before you give the actual speech.Take it as a challenge and not as a work. So you have a challenge and you have to prove yourself. This will give you the needed courage to face the audience. Think of the audience as your friends.