What actually works on LinkedIn for building a waitlist?

We’re trying different things, but would love to know what has been tried and worked for founders here. -Polls - did this do anything in terms of engagement? -Videos - should we be more regular with posting these? -Text posts—so quick to do, but does that do anything for engagement? -Direct outreach - have done it but don't want to be too pushy/salesy. If you’ve built a waitlist on LinkedIn, what actually worked for you?