To switch from another system or spreadsheets, feel free to refer to the Profiles app guide below. Please refer to slides 8 - 10.
As long as you have your spreadsheet of all your employees ready (from another system or from a current spreadsheet that you are maintaining), you can copy and paste the needed fields into the correct rows and columns.
Talenox validates most of the fields in our Google spreadsheet integration to cut down on troublesome errors in importing. :)
(feel free to maximise it to have a clearer view)