The Harry Potter Room...

this 1 is cool. :)

well which house do u like best for ex: griffindor the Стена can be red and yellow или Ты 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 Стена happy decorating

Цвета in yellow, оранжевый and red could be appropriate. Ты may either buy some Gryffindor stuff или make them, for example. или get inspired by the movie Gryffindor Common Room. That is, if Ты feel like belonging to that House. Ты may choose another house, with another set of colours and props.

Depends on how extreme Ты 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 постель, кровати with Hogwarts crest on. Ты can also get posters of the crests for each walls. A HP posters, a Snitch hanged from the ceiling.

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

или Ты can go Great Hall style. Some matte color onto the Стена (grayish brown) and paint candles in eye level and open sky onto the ceiling. Ты can put the crests onto the walls and get HP style час glasses (test tubes filled with colored sand). Posters, scarves, lava lamps (yellow and red ones).

или there's the Black style. Stylish Обои classical furniture Gryffindor and Hogwarts crest, Marauders poster, motorcycle poster, bikini girl poster (or pants guy if Ты are a girl), family дерево (poster или a painted дерево by 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 Ты are, Ты can cut Dobby's and Kreacher's heads from posters and stick them onto the Стена (joking). Black family crest is compulsory.

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

или Harry Style: totally ordinary bedroom with a calendar on the Стена counting back the days till the 1st of September and a whiny bird in a cage. :DD

Good luck.

What house are Ты 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 Избранное 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 Ты 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!

Ты could do something like this i wouldent overdo it too much