A phrase used to explain that the person saying is determined to get what they want. If there is something that they want to achieve they don't just think about it, they go out and do it. This phrase is used to say "I take action and go for the things I want."
"Yo man, Requiem just sits at home all day dreamin' of a better life. As for me.. I go for mine."
I go camping in secret is from the television show "How I met your mother" after Ted tells Robin that he loves her, he leaves and let's her think about if she loves him back. When he wakes up he thinks of what he'll say to Robin and decides to tell her to forget he ever said it. When he exits his room he panics and yells "I go camping in secret!" Which was an allusion to temporary Lyme disease.
I go to school by bus is a piece of comment made by non-native English readers referring to a piece of passage that make no sense. Broadly adapted in Hong Kong since it is a sentence appear in a commonly used primary English language coursebook.