How to sign up for PNP?

I live outside Canada. I filled out the Express Entry application a couple of months ago and waiting.

I see that provinces like Ontario pick applicants in the PNP program every month. Is there anything special I need to do in my application or need to sign up to be in the queue for Ontario’s PNP? Is there a separate PNP application I need to fill up?

Ontario has its own PNP application (and its own PNP application fees) but you will be able to apply to it only if you get invited.