Adding hypens into a group of telephone numbers

A recent question asked
Regarding a column of phone numbers that have been entered without hyphens… Is it possible to highlight the column and put hyphens into the numbers e.g. from 3105551212 to 310-555-1212? If not, is it possible to actually color the middle section of the numbers e.g. the 555 colored so that the 310 stands out as well as the 1212 because they are not highlighted. I am looking for quick way to make the numbers easier to dial because I am receiving spread sheets without the hyphens in the spread sheets.

Couple of options. You can look at the video clips about the LEFT RIGHT MID functions  and then the Concatenate function to see how to add the hyphens. Another alternate is to use the format option to make spaces.