I am not sure that whether this is a right place to ask.
How to earn reputation quickly for a new user?
I am looking for some tips.
There really are no short cuts -- it should be self evident, but the best ways to earn reputation are:
Good questions are well-thought out, and show evidence of research and analysis of the problem.
They also usually involve something that can not be solved/answered by simply reading the manual or typing the title of your question into Google.
Good answers are well-researched. They address the problem and explain best practices to resolve it. They also explain the why, not just the how (teach a man to fish...).
Use some of the advanced search features to find unanswered questions in tags that you believe you are well-versed in or have an interest in.
For example, I like answering questions about Linux so I might perform a query like this [linux] answers:0 closed:0
(link). This will give me lots of unanswered Linux questions that haven't been closed. Then simply browse through the questions, find a question you know the answer for, and provide a good answer.