how; in what way; by what means
Used to ask about the method or means of doing something. Similar to どうして, but どうやって focuses on the way or procedure rather than the reason.
See also: どうして
How do you get to the station?
How do you operate this machine?
どうして asks for a reason ('why'), while どうやって asks for a method or means ('how'), despite sounding similar.
Compound of どう (how) + やって (the te-form of やる, 'to do'), literally 'by doing how'.