It is said that the only way to speak English well is to speak it. However, it certainly isn't an easy task. You will need a lot of time and efforts to practice it. During the long journey on conquering spoken English, persistance is very important for making progress. Read some English materials everyday and memerize the useful words and expressions through keeping notes on a notebook will be helpful. If you can find an environment to speak English a lot like joining a foreign company or having some friends you can talk to in English, that will very beneficial. If you can't, you can still learn by yourself. You can listen to tapes and imitate the pronunciation of native speakers. Then try to take part in some English corners to practice.
Taking an oral English class will surely help with your spoken English but don't put too high an expectation on it. It can help open your mind and your mouth to speak English. However, Rome can't be built in one day. Your own endeavor will be the most important factor deciding if you can learn to speak fluent English or not.
The above is my personal opinion for reference only. Maybe others will have better ideas.