You book the plane ticket, and it's official: You're heading to London!
But what that really means is: You’re heading straight into the heart of the wizarding world.
There are so many big decisions to make. Do you bring the DVDs with you on the flight, or just the books? And which ones?
If you've got Amazon Prime, you can rent any of the books for free on your Kindle, which will lighten your carry-on considerably.
The flight can't go fast enough, and the fact that you need a plane to fly to London makes you feel like such a Muggle.
Though you'll admit that it is kinda magical that you're sitting in a chair 30,000 feet above the ground as it whisks you to London. It's not Floo powder, but it's still impressive.
You land in London, and you're ready to see EVERYTHING.
You're walking near Covent Garden, and there's Knockturn Alley. It's eerily quiet.
It's hidden here, in a tiny alleyway called Goodwin's Court. The walkway is narrow, and there are big gas lamps on the street. There's no way you'd come here at night.
And across the street: The real-life Diagon Alley. There are bookstores and antique shops all over!
It's right across the street and called St. Martin's Lane. Walking through the shops, it's easy to tell how much this street inspired Diagon Alley.
Nothing can get you down — not even the Muggle sights that are way too close to such magical locations.
Honestly, who thought it was OK to put a Chipotle at the entrance to Diagon Alley?
You wander the streets looking for magical places. You tap every brick. Surely there must be some secret entrances here somewhere.
And the signs are everywhere that the wizarding world is all around you. You turn a corner and, hey, it's the Durmstrang ship!
They must be playing a Quidditch match in town this weekend.
You hop on the Muggle Underground — it's what Arthur Weasley would've wanted — looking for more.
There are a few Harry Potter walking tours, so you take one. Two hours later, you're ready to rewatch every film in the series.
I took a tour called the Muggle Tour. It cost £12 (about $19), and my guide knew the movies inside and out. The one downside of the tour: The little kids always got to answer the Harry Potter trivia questions. No fair!
But soon, you start to get disappointed by ordinary, non-magical sites.
This is 10 Downing St., where the Prime Minister lives. David Cameron is no Cornelius Fudge, you realize.
And what's with this money? Pounds and pence? Things would be so much easier if the Brits just used galleons, you think.
You crave even more, so you buy a ticket to the Warner Brothers Harry Potter studio tour, about an hour's journey outside London.
Take the tube to Euston, and then take the train to Watford Junction. It's £5 round trip, and direct trains take about 20 minutes. From Watford Junction, there's a double-decker bus outside the station that goes straight to the studio — it's £2 round trip, and takes 15 minutes.
Or if you want something really simple: There's a direct bus from London that costs £29 round trip.
And then you've got to buy your ticket to the tour itself. That'll cost you another £29 (about $46.50).
Inside, it's all there. The doors open, and you're in the Great Hall.
Everything on the tour is a set from a Potter film. This is the entrance to the real Great Hall that was used during the movies, and it's amazing.
The tables are already set. Can't we just stay and eat? The house-elves are probably cooking anyway!
But there's no food, so you keep walking. Look, there's the Gryffindor common room!
There's the entrance to the Chamber of Secrets!
Look at the Hogwarts portraits!
Why aren't they moving? You tap someone else on the shoulder just to make sure that the portraits are standing still for everyone else too.
There's a spot for you to practice your wand skills. You're waiting in line behind an 8-year-old in a Ravenclaw scarf, and you're just as excited as he is.
After a few minutes, a strange thing starts to happen: You start to feel a sense of the history of this world.
It seems strange to say — you are aware, after all, that Hogwarts is a place that only exists in the mind of each and every person who reads the books or watches the movies — but still, there's a history here. You look at the Daily Prophet headlines and remember the moments that have come before.
Everything here — that pair of Omnoculars, the Knight Bus parked outside — they're all a part of this world that you know and love.
The walk continues. You step outside, and they're selling butterbeer! Real butterbeer!
And you're not just disappointed that Butterbeer is served cold here — you're devastated.
Then you find out that the Butterbeer stand also sells Starbucks. GET OUT OF OUR MAGICAL WORLD, BRANDS.
You walk past Privet Drive. No one is looking at Privet Drive, because who wants to waste time there when there's magic everywhere else?
You keep walking, and you stumble into Diagon Alley. It looks so different from the one in London.
There are broomsticks floating in shop windows, and gag gifts at Weasleys' Wizard Wheezes. It's wonderful.
And then you walk into this room, and it takes your breath away. It's the thing you've been waiting for all along: Hogwarts.
The room is huge, and even still, you're looking at Hogwarts in miniature. But it's there, every tower and bridge and doorway. You start to realize how massive this place is.
There's music playing in the background — the Harry Potter soundtrack, naturally — and you've got goosebumps. It's so big, and so grand. You walk around it, and stare up at it. It's incredible.
You start looking around the room, and you feel a sense of timelessness to this place.
You see people of all ages and races, people from every spot on the globe, and you realize that Harry's world means something to each of them too. Many of the people on the tour weren't even alive when the first book came out, and this story matters just as much to them. That's the real magic of Harry Potter.
Then after three hours of history and magic and possibility and wonder... you step into a gift shop.
It's a bit of a downer. The cheapest thing here is — go figure — the books themselves, which cost about £9. That fake snitch? £12.
Some of the merchandise is really, REALLY tacky, and you're a little embarrassed that it's here at such a special place.
There is Slytherin merchandise for sale, too. You can't understand why it's here. Who self-identifies as a Slytherin? Who is proud enough to walk around in Slytherin colors?
But you're still in awe of this place. And you realize: Your journey into the wizarding world is just beginning.
So you head back to London, and take the tube to King's Cross. You go upstairs, into the main train station. You're not quite sure where to look, but then there it is, right there en route to Platforms 9 and 10.
You grab your belongings at Platform 9 3/4. You collect your breath.
And with all of your thoughts on your friends at Hogwarts, you're finally off.
