SemiSerious, you can use straight fiat on the Populous platform, but using PPT Token gives you advantages.

The idea behind using blockchain technology is to keep everything cheap(no banksters), open, truthful, honest and verifiable for all parties.

edit:
If you know absolutely nothing about cryptos,  

Step 1) sign up at kraken.com and/or coinbase.com

Step 2) transfer fiat to kraken / coinbase to buy Ethereum and/or Bitcoin

Step 3) come back here when step 1 and 2 is done for further instructions

You can trade Ethereum for PPT Tokens at etherdelta.com
https://etherdelta.com/#PPT-ETH

video below explains how to use etherdelta, it's really easy.
https://www.youtube.com/watch?v=PzpeEuPMsL8