How did the philosophies of w. e.b. dubois, booker t. washington, and marcus garvey differ when it came to encouraging african-american civil rights?

Booker T. Washington (1856-1915) advocated gradualism.  That meant being patient and doing what white society would allow, which meant changes and better times for blacks would come slowly.
A different point of view was taken by another leader in the black community: W.E.B. Du Bois (1868-1963).  Du Bois noted that Washington's approach was not accomplishing any real gains for blacks.  He also felt that Washington's point of view showed acceptance of the racial inferiority of blacks.  Plus he saw that institutions in the black community were being dominated by persons like Washington, rather than really empowering all individuals for themselves.  Du Bois argued that all black citizens should have the right to vote, equality as citizens, and access to education according to their abilities, and his approach was more confrontational, attacking segregation using protests, lawsuits, and publications.   Du Bois was strongly active in the National Association for the Advancement of Colored People (NAACP).

Marcus Garvey (1887-1940) founded the Universal Negro Improvement Association (UNIA) in 1914.  He promoted blacks taking power into their own hands, becoming their own business owners rather than dealing with unfairness at the hands of white employers.  He himself opened a restaurant, started a newspaper, and established the Black Star Line, which was the first black-owned shipping company in the US.  "Garveyism" meant black people establishing business and commerce enterprises for blacks as a way of achieving economic independence and success.  In "The Negro's Greatest Enemy," published in 1923, Garvey argued that Negroes were their own worst enemy and needed to take control of their own futures.  He was one of the early figures in what became the black nationalism movement.