No specifics, but my advice is to ask yourself, "Do I want decors that look like what one might find in that world, or do I want blatantly Harry Potter merch?" Personally, for my own home, I avoid the latter because I want it to be a home, not a themed park. For example, instead of having a Slytherin poster, I might feature deep green velvet curtains, moody lighting, maybe a little silver snake doorknob or drawer pull, stuff like that. Basically, a home that looks like it could be something out of HP's world, rather than a teenage fandom bedroom. Not that there's anything wrong with that, it's just that I think it's good to decide which direction you'd like to go towards before deciding how you'd like to decorate. More on reddit.com

Google "Quidditch Beer Pong". There are several versions of this game each which involve throwing the ping pong balls (Quaffles) through the goal hoops and into cups. Different games have different rules about when/how you drink, using 'countercurses' (slapping the ball, etc.). Super fun! Enjoy the party! More on reddit.com

Apart from decorating with wizarding world merchandise, I'd recommend the following: locate your nearest GoodWill (or call up their online auction site on that muggle winterweb thing) and be on the look out for furnishings & decorative elements that evoke a wizarding world / Hogwarts vibe. Try to avoid obviously Wiccan themed or "witchy" rubbish -- that's not wizarding world magic!. Be on the lookout for things that would look like they'd fit in Dumbledore's office or in the potions classroom -- a brass kaleidoscope, a nice wind-up clock or two, maybe a brass telescope, some antique lab glass like a couple flasks, a graduated cylinder and maybe a mortar & pestle. locate your local antique mall and Habitat for Humanity or some other good sized thrift store to get some heavy old wood furniture. A nice side table or chair, maybe a hutch to keep your supplies in and use as a printer station. Of course a nice book shelf! since you're a Ravenclaw, that probably means you're fairly well read and interested in a wide variety of topics. Apart from the Harry Potter classics, put some interesting and magically eclectic books on your shelf. get a nice old brass or ceramic jar to put your quills and spare wands in; a couple antique brass hooks for your cloak, Ravenclaw scarf and academic robes EDIT: since you mentioned in a comment that you're not necessarily looking for a Harry Potter themed office, just use your sense of aesthetics to determine how much HP related stuff you want in the office. I think the rest is still pretty solid suggestions. More on reddit.com

Check out Harry Potter party ideas on Pinterest. More on reddit.com