The main reason one is afraid not to speak out is that they deem that they will talk wrong and people will make a fun out of them, therefore, they prefer to remain quite. Nevertheless, you do not need to worry as mistakes are done by the professionals too. The first and the most foremost step in the learning process is that you need to be confident; it does not matter even if you are speaking the wrong form of English. What matters is that you are speaking and making yourself familiar.
All you need to do is enclose yourself with English. Sit in an environment where all your friends and the colleagues speak English. The more English environment you adopt the better you will learn. Apart from going through the dictionary, listen and watch English songs for better understanding, read newspapers and magazine, Google more and more things, listen to the conversations more effectively. Also, think in English, read books and the novels, write in English. One thing you have to bear in mind is that for any language to learn, you must know that the reading, writing, and listening are the most important aspects of any languages and these aspects play a significant role in the learning process.
Have an environment where only English is spoken; trust me you will pick a lot from such environment if you submerge in it. Learn through the phrases of English and try to understand them. One more thing keeps in mind that, the you see and visualize and get to the conclusions, the more understanding you will develop. See things read them, and further analyze them for a better learning.
However, the story does not finish over here. Use and try to fit in the best phrases and the tenses, no matter you mistakes, a time will come, when will come up with flawless English, keep working hard, practicing more, and struggling too. The more you practice the more expertise you become. It seems tough, though it is not that tough. Go through the dictionary and try incorporating the best words, try to make the sentences and all. Now that you have the entire vocabulary, try to speak to people in English. It may seem unusual but you will love it in the end.