What methods did Malcolm X use to try to effect change?

Before going to prison at the age of 20, Malcolm X was a petty criminal known as Malcolm Little. While in prison he started educating himself and became a convert to the Nation of Islam, taking up the moniker Malcolm X because he wanted to reject the slave name "Little" that was given to his ancestors. He also began to reject many of the pat assumptions of the society he lived in, arguing that African Americans needed to build their own strong and independent communities in order to survive and thrive in a deeply racist America. In this respect he diverged from the other great Civil Rights leader of the era, Martin Luther King, who advocated integration and non-violent resistance.
Malcolm X had a more radical view and didn't necessarily decry the use of violence. His famous quote, "by any means necessary" captures in a caricature his view of what methods were appropriate to affect change and achieve his goals. He advocated a certain kind of black supremacy and was a fierce advocate of black self-determination. Later in his life he had a falling out with the leadership of the Nation of Islam and went his own way, disavowing overt racism (particularly after his experience on the hajj, the pilgrimage to Mecca). He also founded a mosque.
Like King, Malcolm X was a charismatic and fierce orator and public speaker and projected his ideas powerfully. Sadly, his life was cut tragically short as he was assassinated by three members of the Nation of Islam in 1965.