Go to the Todoist integration listing in the Atlassian marketplace.
Select Get it now.
On the next view, choose a site and then select Install app.
You’ll be notified once the integration has been installed. Once it’s been installed, you’ll find the Add to Todoist command in the menu for each issue in Jira.
Note: You’ll need to be an admin in order to add the Todoist integration to your Jira site.