Yeah, this isn’t something you should ever need a guide for, in any game, but this game’s save system is unnecessarily cryptic.
Don’t Give Coins to the Roadside Shrines
The game says that offering a coin to one of the Jizo Statues will quicksave. I don’t know if this is a translation error, or if the game’s designer is just a jerk. Either way, this is a lie. It doesn’t save your game, at all.
Giving a coin to a Jizo Statue just anchors you to that one so that you respawn there if you die. This might sound useful. However, the only way to actually save progress is at the desk in the bedroom, and the door to the house locks when you leave. Luckily, you don’t lose anything when you respawn, and the default spawn point is the bedroom.
You can warp from any Jizo Statue to any of them that you’ve activated (i.e. “talk” to it with or without using it). So, as long as you don’t offer a coin to one of them, you can save your progress anytime you die, and then just use the Jizo Statue to the right of the character’s house to warp back to where you need to be.
There is one possible exception to this rule. In the last chapter, there are Jizo Statues that you just cannot warp back to. The boss sequences in this chapter may be the only time that the “quicksave” function is actually worth using.