I love this question — Dostoevsky's books feel like a small, intense universe, and there's a sweet order to jumping into it. If you want a path that eases you into his voice while building up to the heavyweight moral and philosophical punches, start with 'Notes from Underground'. It's short, sharp, and gives you Dostoevsky's most naked psychological fury in a compact form. After that, move to 'Crime and Punishment' for the crucible of conscience and suspense; it’s more novelistic, with a gripping plot and a character (Raskolnikov) whose internal life will keep you turning pages.
Once you’ve digested those, take on 'The Idiot' — it's a longer, kinder, messier study of goodness and social ruin, and its pacing rewards patience. Next I’d read 'Demons' (also called 'The Devils') if you want political fever, ideological fervor, and a darker chorus of characters. Finish with 'The Brothers Karamazov', Dostoevsky's spiritual and philosophical summit: family drama, theology, and the grandest moral debates. That order builds from intimate monologue to sprawling family epic, so you learn his techniques gradually.
A few practical tips: pick a modern, faithful translation (I like the Pevear & Volokhonsky set for most titles), read slowly and let scenes breathe, and don’t be afraid to reread tough passages. If a long novel is intimidating, read it alongside summaries or a companion guide — I often skim chapter synopses before bed, and it helps. Above all, enjoy the strange company; these books stay with you in small, stubborn ways.