How do I play this exactly? Sanity/Light and Darkness - please explain

[Zoridium JackL]

just a tip, but if you find your running out of oil a lot, it means you are either not using the sprint button, or you are staying in the same place too long, remember to keep moving yet always search a room for goodies, and if you are going to be somewhere for a couple more seconds, you may as well use a tinderbox, if you are smart you won't run out anytime soon, and in regards to the sanity thing, you don't need to be in constant light, but whenever you are moving or searching use it, if you are just waliing through a dim but not dark corridor, then you don't need the lantern,honestly, if it isn't the kind of darkness that is scary, don't bother with light.