Keisei Skyliner

I need to take the Keisei Skyliner from Ueno Station to Narita Airport in a couple weeks.

I've purchased train tickets for the local line where I live and I can just get them at a machine.

Can you do that for this line? Or do you need to purchase them at a ticket counter from a sales person?

If so, should I do this ahead of time or can I do it the day of? It'll be August 10th and I don't live close enough to do it earlier.

You can purchase tickets at the Keisei ticket window.
You can get the Skyliner at Ueno, but it's easier at Nippori. Where are you starting?

I'm starting in Niigata. Google Maps recommended going to Ueno. If getting tickes at Nippori is easier though, I will do that!

It's ok to buy tickets the day of with no problem?

I read online they recommended reservations, but I'm not sure how.

Oh, Niigata. I thought you were starting from somewhere in Tokyo. Assuming you will be on the Shinkansen, at UENO, go up to the street level, walk straight through the concourse to the main street. Turn right and walk around on the sidewalk to the Keisei entrance. You will cross a small street along the way.
I have used the Skyliner many times and it has never been crowded.

Unless for some reason you really have to take the Skyliner, it would probably be simpler to transfer at Tokyo. If you want to avoid the relatively high cost of the Narita Express, you can take an ordinary local train direct from Tokyo to Narita airport.

Thank you Dick H for such detailed directions!

Firas, when I used Google Maps to get from either Ueno Station or Tokyo Station to Narita Airport it only gave me two options. The first was the Keisei Skyliner and the other was a bus, but the bus ride was very long.

Google Maps's public transit navigation is still a work in progress AFAIK, especially in countries other than the US/UK. In Japan, Hyperdia is still the best source.

So yeah, you can take a JR train (either the Narita Express or an ordinary local train) direct from Tokyo station to Narita airport, which saves you the hassle of changing stations from JR to Keisei in Ueno. Also if you use only JR trains, you can buy all your tickets in Niigata.

Not only is the Skyliner faster and cheaper than the NEX, the change at UENO is easier than Tokyo. At Tokyo you have to cross the crowded concourse, then go down 4 levels to the NEX.