I have a reputation of 5 on Stack Overflow. I want to improve my accept rate on Stack Overflow. How can I improve my accept rate?
Only way to do is to start accepting answers to your 28 questions that you asked.
The answers that you think are the best one, click the accept sign next to the answer (below the the voting button). When you click on the acceptance button it will turn green (before that it looks like a transparent "nike" sign).
Doing this will increase your acceptance rate.
Look at this closely related question