If you are inviting your friends to #Mastodon, remember that you can share direct links to a server you believe would suit your friend to sign up to! Make sure it's open for registrations though!

Tell them that when they have signed up they can search for you in the search field by writing [at]nick[at]server (write out your entire handle for them). Or give them a link to your profile and they can add the link to the search field! (press enter)

You can also show them https://joinmastodon.org