Ann: Important notice to unitholders, page-12

After you buy, you setup an account with the Registry who act on behalf of the ASX share you have purchased.

Through the registry you can update details such as how you wish to receive dividends (cash vs re-investment), your communication preferences, bank account details, that kind of thing.

There are 3 main registries who act on behalf of ASX listed companies. VAS and all Vanguard ETFs use computershare (https://www.computershare.com/au).