This project is a skeleton/template design for the ESP-12F module. The ESP-12F is the latest in the series of ESP-12 modules that are based upon the ESP8266 WiFi SoC. The "F" version has an improved antenna design and breaks out all of the SPI FLASH signals. This template design will also work with the "E" version. You can purchase the ESP-12F on Sliexpress for very low cost. It is a great way to get a powerful WiFi microntroller module in your design for less than $2.00 USD.
The schematic has all of the connections need to implement proper startup as well as a serial bootloader via the standard 6-pin 3.3v TTL serial pinout. Starting with this project, you can customize to your liking. The PCB footprint includes a full 3D model that is based upon the ESP-12E (which is 100% mechanically compatible).