Apple sent out notifications to Apple Music users that allows them to send a referral to friend to sign up for a free one-month subscription to Apple Music. Simply tap on that notification to open a page, which gives you a way to send the free access as a gift via text message.
The web page says memberships renew automatically after a month or a month after trial. Apple notes that the referral is valid only for individual memberships.
Last weekend, Apple sent a wave of Apple Music notifications to previous subscribers offering them an additional 3-month free trial.
That means people who have not used Apple Music before can get a total of four months of service for free, because Apple already offers a three month free trial for everyone.
Those who have already used a three month trial and then canceled may be able to get an additional month through this referral link.