Yes, you will need to know someone running an instance to create an account for you.
So... no? :)
Yes, you can try it without running your own instance. You will need to use someone else's instance.
Presumably if the protocol becomes popular you will have public instances that anyone* can sign up to, the same way other federated services work now.
(It's approximately as hard for a layman user to sign up to a Mastodon instance as it is to sign up for X. The fact that most layman users don't do that is a separate issue.)
If you (top and child commentator) want to try without running your own, please send me an email: david dot collantes at gmail dot com.