GGPLOT LEGEND code example
Example 1: ggplot legend title
+ labs(color='NEW LEGEND TITLE')
Example 2: how to change labels on legend ggplot
scale_color_manual(values = c("#D16103", "#4E84C4"),
labels = c("Justin", "Myself"))
Example 3: ggplot legend size
plot + theme(legend.key.size = unit(2, "cm"))
Example 4: ggplot put legend in plot
p + theme(legend.position = c(0.8, 0.2))