If you have space to create a new char, you can fly that new char to Jita and get the PLEX, activate the PLEX on that new char, since the PLEX will activate the account. Which char you wish to train skills on is up to you.
Else I hear something about donate a a PLEX, not sure how it works, but can look into it if you don't have space for a new char on your account.
I can sell you a plex in Jita 4-4 for 800 fg
This post was edited by XtCi on Mar 8 2016 09:56am