I am a computer science graduate,I have been doing job but in the weekend I got bored,My question is how can I make money  through internet by working in the weekend ,I have decent knowledge of programming in c++ and I am computer science graduate?

I don't mean to offend you but here is my take, You want to profit through the internet, which currently, is all about social media, a.k.a. communication. The language you are using to communicate your intention across is typical to your region (India) For example, "I have been doing job." Your likely targets are spread across the world and may or may not understand your linguistic idiosyncrasies. So try and universalize your language skills. I am not judging your language style, because as an Indian, I know that we are like this only bass! So the short and sweet answer is, fine tune your pitch so that it appeals to most audiences.