I wasn't always able to buy a ticket on the tram. In some cases I couldn't fight my way through the masses to get to the conductor. I'm pretty sure there wasn't a conductor on an early morning train I took too, but I may have just been too tired to see them

At all of the stops I saw, there were clear maps telling you what the upcoming stops were. You shouldn't plan on relying on the announcements/signs. I was on several trams where I could barely hear the noise from the speaker.

I don't know if the conductors sell the multi-day cards, or if you have to get those at a ticket office somewhere. I wasn't able to find a ticket office/kiosk/machine at the airport, and that was pretty surprising to me.