The BBC recently came up with a list of things you should perhaps not do when on Facebook, many of which relate to employment.
The five include:
1) Make friends with people you shouldn't.
2) Moan about your boss/customers/constituents.
3) Upload dodgy photos.
4) Enjoy your sick leave too much.
5) Spill secrets.
For more details see Facebook: Five things to avoid by Marie Jackson.