Wax シール
Paper (You could use regular paper and give it a tea/coffee effect または あなた could use parchment paper. (I used the parchment)
These Harry Potter FREE Fonts found here. (You can pick and choose which ones あなた want. There is no wrong way to do this, I promise)
Address Labels (this is to print out a faux wax seal)
Twine (optional)

Find out more...

The first page of the acceptance letter says:

Hogwarts School of Witchcraft and Wizardry
Headmaster: Albus Dumbledore (Order of Merlin, First Class, Grand Sorc., Chf. Warlock, Supreme Mugwump, International Confed. of Wizards)
Dear (Your name)

We are pleased to inform あなた that あなた have been accepted at Hogwarts School of Witchcraft and Wizardry. Please find enclosed a 一覧 of all necessary 本 and equipment. Term begins on September 1. We await your owl によって no later than July 31.
Yours sincerely,
Minerva McGonagall
Deputy Headmistress

The 秒 page with requirements says:
Hogwarts School of Witchcraft and Wizardry
First-year students will require:
1.Three sets of plain work robes (black)
2.One plain pointed hat (black) for 日 wear
3.One pair of protective gloves (dragon hide または similar)
4.One winter マント, 隠す (black, with silver fastenings)
Please note that all pupils' clothes should carry name tags.

All students should have a copy of each of the following:
The Standard Book of Spells (Grade 1) によって Miranda Goshawk
A History of Magic によって Bathilda Bagshot
Magical Theory によって Adalbert Waffling
A Beginner's Guide to Transfiguration によって Emeric Switch
One Thousand Magical Herbs and Fungi によって Phyllida Spore
Magical Drafts and Potions によって Arsenius Jigger
Fantastic Beasts and Where to Find Them によって Newt Scamander
The Dark Forces: A Guide to Self-Protection によって Quentin Trimble

1 wand
1 cauldron (pewter, standard size 2)
1 set glass または crystal phials
1 telescope
1 set brass scales
Students may also bring an owl または a cat または a toad.

あなた can copy and paste the above wording into a Word document. Don't forget to personalize the letter before printing または to give Professor McGonalgall an エメラルド signature. あなた can also copy the image of the Hogwarts シール and paste into a word document.

Once あなた have it on your Word document and あなた have downloaded the fonts あなた can change the font of wording. Remember, there is no one way to do this. あなた can choose any font to use.

The envelope could have the following information:
Name: Mr. T. PAIN
Bedroom location: On a boat, on a big blue watery road
通り, ストリート address: 123 Water Street
City, State: New York, New York
Country: USA

This, of course, is an example. あなた would put in your info. あなた could use a regular envelope または make one from paper using a tutorial like this.

Then あなた can copy and paste the シール below and print it out on an address label. Cut it out and use it on the back of the envelope as if it were a real wax seal.

{Credit : www.hellopapermoon.com/2012/06/hogwarts-here-i-come.html }