For accepting online orders/sales. Enabling your site's Donate Now page activates an online form: [your site url] /give which allows your supporters to donate money and/or purchase items without attending an event.
Check out the Demo site for an example of how the software can be set up to accept online orders/sales, then follow the instructions below to set up your own site/page.
To set up a page for online orders/sales:
Go to: Admin > Site Settings > Online Donation Forms > Donate Cash and Online Store