When a speaker uses the words you, yours and yourself, she is using first person.
But, when an author uses the words you, yours and yourself, she is using third person.
Why?
The speaker is speaking to you directly, in real life. She is looking at you, pointing to you, talking to you. She is talking to Jacoblynch412. You.
The author is speaking to anyone in particular that is reading the book. Not you directly.
I hope this was helpful! Please tell me if you need any more help.