Last year I was able to get it working by looking at examples like https://github.com/lewapek/sds-dust-sensors-arduino-library and the datasheet https://cdn.sparkfun.com/assets/parts/1/2/2/7/5/Laser_Dust_S...
There's a nice walkthrough here: https://www.hackster.io/taunoerik/using-sds011-dust-sensor-0...