Start out by unlocking double assassinate in the shinobi tree, it's honestly essential for taking down two guards silently. The smoke bomb and shinobi bell skills are your next priority, making it much easier to control groups and pick off isolated targets. While you're learning the basics, keep to the shadows and remember that extinguishing lights creates more dark spots to work with.

Getting good with your tools makes everything smoother, especially the kunai for silent ranged kills. A nice thing to know is that you can actually retrieve them from bodies to save resources. The shinobi bells are perfect for drawing guards away, and combining that with eagle vision to spot enemies through walls gives you complete control of each situation.

For the fastest skill gains, make your way to the kuji-kiri trials when you can since they're focused entirely on stealth practice. The forge should be one of your first structure upgrades, letting you improve all your sneaking gear, and establishing kakuregas gives you safe spots to restock. Night raids are always easier to pull off, and remember to hide bodies in water or bushes to keep patrols from getting suspicious. Eagle vision really shines here, helping you track guard movements without breaking cover.