How to Obtain All Achievements and Collectibles
The First Chapter
Fair Prey achievement
Equip the hunters hat and wear it for the duration of the part of the level where you run and hide from the hunter (I equipped it for the whole level but I think it still works if you keep the hat from the moment that you find it).
The first Glitching Remains  is right after the broken bridge (where you have to climb down using the rope). Instead of going up, go to the right and you'll see a little tunnel that leads to the first shadow person.
Evasive Prey achievement
You need to pass the bear-trap section without dying. The section starts right here:
After sliding down the log on the previous image turn back and go under it to get the next Glitching Remains .
When you reach the hunters cabin go towards the fridge and open it to get What's in the box achievement
After you go in the hallway, go towards the camera and to the left to get the Hat .
Equip the hat and don't take it off until the end of the level to get the achievement Fair Play!
Continue on with the main story until you exit the hunter's cabin. The next Glitching Remains  is in the outhouse right outside hunter's cabin. To open the door walk towards it until Six gets into position for boosting you up, then you can open the door.
Continue on and the next hat will be right after this bridge:
It's in the cage up top (I already collected it so it's not on my screen yet but I'll change the image a bit later):
Climb up there and jump on the cage several times to break the rope and get the Hat .
Continue on and after you cross the water, you'll find the last very obvious Glitch Remains  in front of the TV (not on my screen yet but it's where the character are, I'll change the image later).
- Upon finding all the Glitching Remains in the first chapter, you'll get the Wild Kids achievement.
- After you end the chapter, you'll get the Foraged achievement.
- Also, right from here you can get the Twenty-Six achievement by calling Six twenty-six times (or you can get it later on as well).
- And In The Palm Of My Hand achievement by holding Six by her hand for approximately 6 minutes without letting go.
The Second Chapter
At the start of the chapter you'll throw down two TVs. When you'll throw down the second one so Six would be able to go up, get to the floor above you (where Six ended up), there will be the first for the chapter Glitching Remains 
When you reach the school grounds, you'll find the second Glitching Remains  in the background sitting near the dempster (you can see them only when you approach them):
The Hat  will be lying on the dumpster right in front of the stairs:
Pick it up and equip it. While this hat equiped, run through the football gates to earn the Referee achievement.
Go inside the school. You'll end up in the hallway. Run in the room in the back of the corridor and pick up the paper plane:
You'll need to take it all the way back to the window you came from and throw it in the window to get the Fly Free achievement
After you get separated from Six, go forward until you see the elevator. In one of the lockers to the left of it hiding Glitching Remains . You'll need to open the locker to get it.
When you reach the classroom, you'll have to sneak past the teacher. But in order to get the next achievement, you'll have to get noticed, get in the room to the right, start climbing the shelf and make it fall on 3 kids to get the Bully of Bullies achievement.
If you are having troubles getting it, the easiest way is to sneak all the way to the room with the bookshelf. Wait until the teacher stops writing, get back in the classroom and immediately back in the bookshelf room (you'll get noticed but will have an ahead start to start climbing). Start climbing all the way and don't jump off (even if you die with them, you'll get the achievement). This way they will all be grouped up under the bookshelf.