Everyone else must get very wet! While driving around in one of the mini-buses we saw the two Knight buses, only one is drivable. There were all the props from the Riddle graveyard piled up and train tracks across the grass where the Hogwarts Express had been filmed. Usually it is filmed elsewhere but it was dismantled and assembled there on tracks laid by Railtrack (or something). There are large grass areas near the canteen and they told us the cast and crew play golf and football there in their free time.

We were shown the Hogwarts gates; they are in a small clump of trees with the tops lopped off and have blue screen on each side (blue instead of green because of the trees and grass). The spikes on the gate are made of rubber for health and safety reasons! There are huge carved griffins on top of the gate columns. They said the GCI will be added later with Hogwarts castle on one side and the trees will be repeated to make the Forbidden forest.

Hagrid's hut was a short bus ride away, it had been burned, even saw Hagrid's pumpkin patch though there were no pumpkins. They filmed it burning with a load of cameras (I forget how many they said) because they only got one chance to film it burn. A lot of the outdoor sets have camouflage nets around them. This is because the neighbours complained that the light was reflecting off them and that they were ugly.

I saw The Burrow both the inside and outside sets; the outside set had been burnt out in a Death Eater attack. The inside of The Burrow was amazing, the attention to detail. I climbed up the stairs to Ron's room, the bedrooms aren't there but the corridors have doors coming off them with pictures and ornaments. One of the doors had a picture of mushroom on it. Downstairs there were two clocks, one with the whole family's names on and scissors for hands, the other was smaller with a list of jobs to do. There were even postcards to Ron on the bookcase, howlers (or just letters like paper aeroplanes), a wizarding newspaper on a coffee table and children's paintings of magical creatures framed on the walls. The guy showing us around said that it was the hardest set to build because nothing was straight or regular sized.

We went into the Great Hall, it really was huge. There are still wires hanging from the ceiling for the candles from the first film and they use them as reference points. The tables are oak and seat hundreds in sets of tens. All the side walls have false doors in to allow speedy entrance and exit of the large cast. We took our pictures (sob) standing on the dais in front of the teachers table. The tables were laid out with cereal (Pixie Puffs and another was a play on Cheerios) and gold plates and goblets. The windows are made of sugar glass and apparently take a week to clean. There was talk of blowing them up in this film but they changed their minds. They don't use any real food anymore unless a cast member has to be seen to be eating; even the butter that sat on the table was fake.

The Gryffindor common room was quite small. It is still the exact same set from previous films. As you walk in the door (no picture frame entrance here) there are a set of pegs on the right with Gryffindor cloaks, bags and someone's tie hanging up. The picture frames are filled with green screen and all the furniture is from auctions. Usually they hire furniture but as it was going to be used for so many years, this time they bought. All the chairs are well worn and a bit tatty! There was a little seating area to the left in a window alcove and the fire where Harry spoke to Sirius is on the right. Straight ahead are the stairs to the boy's bedrooms. They spiraled upwards to the left but to the right were a few steps that didn't go anywhere. At the top of the stairs there was a small hall from which you could look down into the common room over a banister. In the bedroom all the beds have been cut in half and extended as the films have gone on as the cast have grown too big for them! The curtains around the beds are velvet with star prints on them. The beds had roman numerals painted on the top in gold which corresponded with the numbers painted on the bedside tables, a nice touch. The tables had knickknacks on them and every bed had the correct trunk under it except Harry's which was at the Burrow. Dean's bed had West Ham covers on it.

We walked around Diagon Alley. Ollivanders had been destroyed, all the windows were smashed and it was trashed. The shops had complete interiors in case the camera caught a glimpse inside by accident. Quality Quidditch supplies had a Quidditch equipment display, uniforms on dummies and drawers full of clothing. Florean Fortescue's had fake ice cream sundaes lining the walls on shelves. Florish and Blotts had hundreds of books inside the doorway piled up and on shelves. The large books in the windows are actually Watford phone directories covered!

But Weasleys' Wizard Wheezes stood out in bright orange with a curved front door. It was the most wonderful place. It was like every dream you had as a kid. There were skiving snack boxes, puking pastels, U-no-poo, sweets from floor to ceiling. It had a set of stairs winding up the middle and was three floors high. The detail was amazing; the shelves were crooked with brightly coloured goods on every surface. It was truly breath taking. At the end of our tour we watched them filming a scene there. When you see the scene where Fred and George are talking to Ron on the stairs, he asks how much for an item, they say '5 galleons', Ron says 'but I'm your brother' and they say '10 galleons'. Well I am standing behind the stairs (out of sight) by the door! It took eight takes just for that few seconds and I was told they only complete 2 minutes of film a day.

We saw Knockturn Alley but the lights weren't on so it was by torch light! Saw Borgin and Burke's that way. The vanishing cabinet was in the centre, it was dark wood with a slanted roof. There were lots of skulls and creepy looking objects – even creepier due to the lack of lighting. There were wanted posters on the alley walls for Bellatrix and the Carrows.

We couldn't get into moaning Myrtle's bathroom because it was locked. They filmed the Sectumsempra scene there last week. They told me Tom had to lie in the fake blood and water for hours. He had a prosthetic chest on which pumped out fake blood and for each new take he had to get cleaned up and dry his hair before starting again. There are some pictures floating about of the scene and they look like Tom is lying dead in a pool of blood, very freaky for his friends to see!