We use Edinburgh-based Citizen Ticket who are managing our box office and hosting our livestreams for online events.
After you have bought your tickets, confirmation will come through in an email with information on it that looks something like this:

Your tickets explained
Citizen Ticket will then send information on how to access your event. Access will require you to create an account which will create a unique “ticket wallet” for you where all your tickets (and links to the livestream) are stored. Once you have created an account, you will be able to access all future tickets straight from that site.
If you don’t have an account, you can create one HERE with a name, email and password. Once you have created an account and verified your email address, you can access it from HERE. If for any reason that does not work, you can reset your password on the same page. More Citizen Ticket FAQs can be found HERE.

This email will come with a QR code attached for in-person events only. These may be scanned directly from your mobile or from a paper print-out at reception during entry. A print or online version of your ticket will also gain you entry to the event in the usual way.
You can access your tickets from your ticket wallet. Your ticket will look like this:

Live in person events: At the door before the event, use the QR code from a mobile or a physical print-out.
Online live stream: There will be an option to watch live from your ticket wallet. Otherwise, use the ticket by clicking on the name of the event (left hand side, beneath the QR code) and choose watch live.
Pre-recorded livestream: Choose watch again and you will be taken straight to the streaming page.
For advice on how to get the best from your online concert experience, click HERE