How about some old-school table showing predicted means? (See below)

Once you have all these data, it's possible to plot them. Use Negative > Neutral > Positive as the x-axis, predicted RET on the y-axis. And experiment different ling layouts:

1. All eight lines: possible if they separate from each other very clearly.
2. Four lines on each graph, two panels: For instance, split the graph by litigation yes/no, then then within each use colors to represent pollution, and line styles to represent layoff.
3. Two lines on each group, four panels: Suitable if your eight lines are really close and messy.

How about some old-school table showing predicted means? (See below)

Once you have all these data, it's possible to plot them. Use Negative > Neutral > Positive as the x-axis, predicted RET on the y-axis. And experiment different ling layouts:

1. All eight lines: possible if they separate from each other very clearly.
2. Four lines on each graph, two panels: For instance, split the graph by litigation yes/no, then then within each use colors to represent pollution, and line styles to represent layoff.
3. Two lines on each group, four panels: Suitable if your eight lines are really close and messy.

I don't think you have a line because all your predictors are categorical. How about some old-school table showing predicted means? (See below)

Once you have all these data, it's possible to plot them. Use Negative > Neutral > Positive as the x-axis, predicted RET on the y-axis. And experiment different ling layouts:

1. All eight lines: possible if they cluster very clearly.
2. Four lines on each graph, two panels: For instance, split the graph by litigation yes/no, then then within each use colors to represent pollution, and line styles to represent layoff.
3. Two lines on each group, four panels: Suitable if your eight lines are really close and messy.

How about some old-school table showing predicted means? (See below)

Once you have all these data, it's possible to plot them. Use Negative > Neutral > Positive as the x-axis, predicted RET on the y-axis. And experiment different ling layouts:

1. All eight lines: possible if they separate from each other very clearly.
2. Four lines on each graph, two panels: For instance, split the graph by litigation yes/no, then then within each use colors to represent pollution, and line styles to represent layoff.
3. Two lines on each group, four panels: Suitable if your eight lines are really close and messy.