Using PWM for a clock is one way - there are other ways depending on what frequency you intend to use to clock the microphone.
There are other design considerations that you need to make. For example, you say you want to send the audio data to HyperTerminal - how? HyperTerminal is a terminal emulator that is used to display (and enter) characters. How is that expected to display the 'audio data? A fast stream of numbers???
Even before that, the PDM information needs to be converted to analog, or at least an equivalent digitised data stream. Presumably the sampling rate will be related to the microphone clock speed. The PDM stream is simply a stream of 0's and '1' - single bits - that need to be converted to an analog value (as per the Wikipedia article I referred to above) by a LPF. Of course this can be done digitally but you then need to convert the values to digital but the sampling rate can be quite different to the microphone clock rate.
For example, speech via a telephone can be limited to a bandwidth of 300Hz to 3kHz to be understandable. That means a sampling rate of at least 6kHz. On the other hand, CD quality audio is sampled at 44.1kHz.
Then there is the question of how many bits to each sample - 8? 16? 24?
What sampling rate do you intend to use?
Even at 6kHz sampling, and assuming 8 bit samples, that is still approximately 6600 BAUD needed to transfer the values as binary to the HyperTerminal (which may balk at trying to display that). If you try to convert it to a displayable ASCII stream, and assuming 4 characters per sample (3 for the values from 0 to 255 plus a delimiter) that means a transfer rate to the HyperTerminal of greater than 240,000 BAUD. This is certainly achievable but is it what you really want?
Susan