There isn't an "easy" solution, but step 0 is recognizing that there is an historic problem that is being dragged with us into the future because of the way our current systems work.

Political solutions are necessary, maybe something like subsidized loans for people from formerly redlined communities to purchase and restore homes, or start businesses. Urban planning projects, like increasing mixed-zoning, pedestrian traffic, and good public transportation would help keep money in the neighborhood. Then there is the question is how to deal with gentrification and increase quality of living in a community without displacing people from that community. It takes a team of experts from various fields, the community itself, and goal-oriented cooperation.