You will learn how to conect sensors to esp8266
For this tutorial we will need:
On pic you see how breadboard works
To use DHT22 you need appropriate library to read sensor data.
Download one here.
Install the library (follow instructions in Read-me file).
Open Arduino IDE and check that it's in a new library added to "File"->"Sketchbook"->"libraries"->"DHT22".
Open example code for DHT library by clicking on "File"->"Examples"->"DHT"->"DHTTester".
Press upload and wait to arduino finish uploading code
Open serial monitor and see values from esp8266 reading dht22 sensor.