Basically the easiest way to setup your mic in teamspeak is when you go to Tool -> Options -> Capture and then choose your capture device (the mic you are using).
I recommend you setting up Push to talk aswell. (Its pretty simple so I dont really think I have to explain it If I do msg me).
After that you just "test" your mic, you will have the option under "capture" too or you can use Chow meins option to test your mic.
If I missed something let me know.