Each event's worker signup has its own link. Share it when you need more workers for one event, through Bound announcements, social media, or email. Workers who open the link go to that event's signup page.
Note: Workers can sign themselves up only when the signup has Open Signup (allows workers to freely sign up) enabled, and only for shifts whose permission they have.
Copy the Link
Go to Events -> Workers -> Event Setup.
On the Signups tab, click the green button next to the event's signup.
Click Manage Workers -> Copy Signup Link.
Paste the link into your announcement, post, or email.