Allyship is a process, most notably a learning process. Allyship involves a lot of listening and is sometimes referred to as "doing ally work," "acting in solidarity with," or "being an accomplice" to reference the fact that "ally" is not an identity but rather an ongoing and lifelong process and commitment to action that involves a lot of work.
An ally acknowledges the limits of their knowledge about oppressed people’s experiences but doesn't use that as a reason not to think and/or act. An ally does not remain silent but confronts oppression as it comes up daily and also seeks to deconstruct it institutionally and live in a way that challenges systemic oppression, even at the risk of experiencing some of that oppression. Being an ally entails building relationships not only with people oppressed by their identities but also with people privileged by their identities in order to challenge them in their thinking. (Source: Simmons Anti-Racism Research Guide)
Allies don’t have it all figured out, but are committed to non-complacency.