Hello,
I am trying to create a map of Michigan with some particular counties highlighted. Which I have done so here:

The code I'm working with is:
#create Michigan map
library(ggplot2)
library(ggmap)
library(maps)
library(mapdata)
states <- map_data("state")
michigan <- subset(states, region= "michigan")
mi_df <- subset(states, region == "michigan")
counties <- map_data("county")
mi_county <- subset(counties, region == "michigan")
mi_study_counties<- subset(mi_county, subregion %in% c("chippewa", "cheboygan", "delta", "schoolcraft", "otsego", "menominee"))
mi_base <- ggplot(data = mi_df, mapping = aes(x = long, y = lat, group = group)) +
coord_fixed(1.3) +
geom_polygon(color = "black", fill="white")+
theme_void()
mi_base
mi_base+ geom_polygon(data = mi_study_counties, fill = "gray", color = "black") +
geom_polygon(color = "black", fill = NA)
What I need help with is labeling the county names on the counties that I have highlighted. Also, is there a way to do a fill of different colors for the different counties? Like fill 3 of them gray and 3 of them blue? Any help is greatly appreciated!