Kingdom Come: Deliverance is a challenging RPG with consequences for every decision that you make. With that, Warhorse Studios chose a design for saving progress that discourages abuse and encourages players to choose wisely. There are infrequent autosaves if you're on the main quest thread, but there are a couple different ways to manually save your game.
Save Your Progress With Saviour Schnapps
If you want to save your game by pausing and hitting "Save Game", you'll need the alcoholic beverage known as Saviour Schnapps. You receive a couple bottles early in the game but, once you've used them, they can be a bit pricey to purchase. Taverns in the towns will have some for you, but the price is typically enough to make you think twice about buying.
You also run the risk of becoming an alcoholic, which impacts how your player controls, how every NPC perceives you, and more. If you become dependant on it, it could hinder your playthrough in a big way. This brings us to the other way to manually save your game: Sleep.
Save Your Progress By Sleeping
If you lay the character down in a bed, on a blanket, or wherever you find yourself sleeping, the game will save when you rise. This will keep you from flying through the very meager currency you'll earn in Kingdom Come: Deliverance, but it isn't full proof. You can't sleep just anywhere.
There has to be a space dedicated to the player and sleeping in a random NPC's dwelling isn't viable, considering you'll be trespassing. As with many of the game's elements, you must plan things ahead of time. A lot of the game's events move at a realistic pace during the expected times of day and some quests will explicitly tell you when you can access something. Plan accordingly and keep your player well rested, as energy will deplete as you play.
Kingdom Come: Deliverance launched today on PC, Xbox One, and PS4. Kingdom Come: Deliverance is a large and complex sandbox with many gameplay systems and areas to explore. Check out our ever expanding Kingdom Come: Deliverance Guide and Walkthrough article for ways to keep you survive this dangerous world.