The Harry Potter Room...

this 1 is cool. :)

well which house do u like best for ex: griffindor the ウォール can be red and yellow または あなた can do a darker shade of blue and get some harry potter fatheads (wall stickers) and some glow in the dark stars that stick to the ウォール happy decorating

Colors（色） in yellow, オレンジ and red could be appropriate. あなた may either buy some Gryffindor stuff または make them, for example. または get inspired によって the movie Gryffindor Common Room. That is, if あなた feel like belonging to that House. あなた may choose another house, with another set of colours and props.

Depends on how extreme あなた want to go.
4 walls, 4 houses - two thick stripes vertically. Red and Golden for Gryffindor, silver and green for Slytherin, etc. Black cover onto the ベッド with Hogwarts crest on. あなた can also get posters of the crests for each walls. A HP posters, a Snitch hanged from the ceiling.

または あなた can select a house and go after that: leather stuff with some vintage 壁紙 (gray background green pattern) with green border/dark yellow walls with red border and Gryffindor crest, red chair, carpet in Victorian style...

または あなた can go Great Hall style. Some matte color onto the ウォール (grayish brown) and paint candles in eye level and open sky onto the ceiling. あなた can put the crests onto the walls and get HP style 時 glasses (test tubes filled with colored sand). Posters, scarves, lava lamps (yellow and red ones).

または there's the Black style. Stylish 壁紙 classical furniture Gryffindor and Hogwarts crest, Marauders poster, motorcycle poster, bikini girl poster (or pants guy if あなた are a girl), family 木, ツリー (poster または a painted 木, ツリー によって your own lil hands with pictures of Bella, Malfoys etc above the names). And a name board onto your door like Regulus Arcturus Black. Dependant on how hard core あなた are, あなた can cut Dobby's and Kreacher's heads from posters and stick them onto the ウォール (joking). Black family crest is compulsory.

または Ron one... Quidditch oriented. Harry playing, Cannons poster, Viktor Krum poster, Irish Hat, textile Clovers, brooms, Snitch hanged from the ceiling.

または Harry Style: totally ordinary bedroom with a calendar on the ウォール counting back the days till the 1st of September and a whiny bird in a cage. :DD

Good luck.

What house are あなた in!?

Thats a big deal, like Im Slytherin, so I have green walls in my bedroom, with like a silver and green bed-set. I have snake-themed furniture and a slytherin pillow/throw blanket. (You can buy those online for any house.)
I have Harry Potter posters on my walls, and I painted some of my お気に入り quotes.
And the Deathly Hallows symbol is also painted there.

Over my bed, I have the Hogwarts crest (its like a REALLY big sticker I bought online)

Thats what I did. But あなた could do something similar, with your own personal favorites. (If ur not a slytherin, change the colors, my posters are Severus, Draco, Bellatrix etc, so if those arent your favorites, change them!

あなた could do something like this i wouldent overdo it too much