Materials
Before you begin purchasing materials, I would like to go over certain skillsets that are required to build this drone. One of the most important ones is just having some experience with the Arduino. It helps one understand basic power electronics how to use breadboards, and how circuits work. If you have no experience with Arduino, I have recommended an Arduino kit in the flight controller section. Try out some of their projects before jumping into this one. Another skill I recommend is knowing how to solder. This is not an necessary skill for I learned how to solder throughout this project, but coming in with the skill will save a lot of time. Understanding basic power electronics is also a plus but you could easily pick up that skill with the Arduino kit and also through many of the tutorial links that will be included in this guide.
Finally, if you want to understand PIDs, which is the name of the algorithm that is behind self-balancing quadcopters, you will need a solid understanding of calculus and physics. However, this is not needed to build this specific quadcopter since the code is pre-written and is available for a direct download onto the Arduino. If interested, I will be explaining PIDs in simple terms, and the code is very documented so you are able to see where they come into play.
This will be a very in depth materials list. I would like to explain all the basic parts needed to build any quadcopter, not just this one. When shopping on amazon, the name for the products are extremely long and have many numbers and abbreviations you might not be familiar with. If any of the materials become unavailable, remember there are other sellers on amazon that sell the same product although it might not be available for amazon prime. Refer to the dropdown menu under materials to quickly navigate to a specific component and get more information. There are other components needed to build and maintain the quadcopter and those are linked in the Additional Materials section. The main components are listed below.
Summarized List
Frame
ShareGoo DIY X525 V3 Fiberglass Quadcopter X-copter Multirotor Foldable Frame Kit + 1 Strap
https://www.amazon.com/gp/product/B073WYJ2Z8/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1
Brushless Motors and Propellers
Crazepony® 4pcs Emax Mt2213 935kv Brushless Motor with Orignal 1045 Propller for DJI F450 F550 Quad Hex Octo Copter 2CW 2CCW
Inertial Measurement Unit
GY-521 MPU-6050 MPU6050 3 Axis Accelerometer Gyroscope Module 6 DOF 6-axis Accelerometer Gyroscope Sensor Module 16 Bit AD Converter Data Output IIC I2C
Electronic Speed Controller
2-4S 30A ESC SimonK Brushless Motor Speed Controller ESC With BEC 2A for Quadcopter Multicopter(4PCS)
Power Distribution Board
GEPRC-XT60 PDB Power Distribution Board with 3-6S Input 5V 12V Output Support the LC filter for FPV Racing Quadcopter Frame
Battery
FLOUREON 3S 11.1V 2800mAh 35C Lipo Battery Pack with XT60 Plug for RC Airplane RC Helicopter RC Car RC Truck RC Boat, RC Hobby
Transmitter and Receiver
GoolRC OEM GC6 (Custom Flysky FS-i6) 2.4G 6CH Transmitter and GC-6 6CH Receiver with Carring Bag&Neck strap for RC Helicopter Multicopter Fixed-wing Mode 2
Flght Controller Arduino
Elegoo EL-KIT-003 UNO Project Super Starter Kit with Tutorial for Arduino
https://www.amazon.com/Elegoo-EL-KIT-003-Project-Starter-Tutorial/dp/B01D8KOZF4/ref=sr_1_1_sspa?ie=UTF8&qid=1526859885&sr=8-1-spons&keywords=arduino&psc=1
I recommend getting the kit linked above if you have no experience with Arduino. Try out some of the projects they have designed. I also recommend getting this kit because it includes several small components you will need for the build. However, if you would like to just buy the Arduino itself, Amazon has many different sellers that sell the Arduino Uno at a range of prices.