ESP8266 module is a great wireless module with some processing power and I/Os. Especially if you are new to it you may find some things not clear enough or struggle while programming, uploading firmware or simply configuring. Rui Santos have written a troubleshooting guide on how to avoid those common obstacles. He talks about where to download NodeMCU flasher, how to configure its settings.
Other most common pitfalls also are covered that might frustrate you. Even unbricking of FTDI programmer is covered. If you find yourself in desperate situation when trying to run ESP8266 this troubleshooting list may save you tons of time.