I understood what you wanted somewhat differently than @zach. Here I use the interaction
function to create a new factor with the four levels you specified. Here using some dummy data
set.seed(42)
sex <- sample(c("Male","Female"), 20, replace = TRUE)
navigation <- sample(c("menu","tags"), 20, replace = TRUE)
interaction(sex, navigation)
the last line gives
> interaction(sex, navigation)
[1] Female.tags Female.menu Male.tags Female.tags Female.menu Female.tags
[7] Female.menu Male.tags Female.menu Female.tags Male.tags Female.tags
[13] Female.menu Male.tags Male.menu Female.tags Female.menu Male.menu
[19] Male.tags Female.tags
Levels: Female.menu Male.menu Female.tags Male.tags
Is that what you wanted?