How do I organize a New Year's Eve party at home?

The most important thing is to plan ahead: figure out how many people are coming, what you'll have to eat and drink, and arrange your space to feel welcoming without needing a lot of room. Make a playlist with music everyone likes, prepare something easy to eat (snacks, cheese boards, stuff you can make in advance), and stock drinks for everyone. With limited space, keeping it more intimate with close friends works well - board games or just hanging out and talking; the vibe of the party really depends more on who's there than how big the place is. Give your friends enough notice so they know what to expect and can confirm they're coming.