You can buy them on counterparty right now.
When the project is fully developed you will have to deposit your NVST on your NVO Wallet so you can receive the NVSX (dividends-like).
On this excel sheet, you can input the volume you estimate NVO may do on a daily basis and how much NVST you hold to find out the possible revenues you could have theoretically.
On the right of the table, there is an history of the top 20 volume since June.
https://docs.google.com/file/d/14r4-vS69G1CbtqRaVQYQ1z0z6BI8fVVO/edit?filetype=msexcelNVSX distributed on a weekly basis fyi.
Very cool, thanks for sharing.