The proposal pdf preview offers the button: Close with attachment - which will save your file to the Attachment related list in your media campaign and for lightening users also in as a file. (Starting version 2.82)
Open the activity Send Email on the right of your record:
Open the contact you wish to send the order confirmation to. Create an email as usual. Then attach the order confirmation to the email:
will open a new window where you can enter your recipients. (In Lightning use the standard email component and predefined templates to email the attachment to your clients).
With order confirmations created as PDF and the ADvendio.com system's integrated email function, it's easy to send order confirmations to your contacts.
Go to any media campaign and open the order confirmation. Then hit the button "close with Attachment" on the order confirmation. See 4.7.1 Create Order Confirmation. In Classic you can then push the button "Send via Email" to email to your contacts.