I tend to follow the instructions in the service manual, as they will vary with application, gasket material, and so on.

Valve cover gaskets were always glued on the cover in the old days, left dry on the other face so you could take the valve covers off without destroying the old gasket. Paper gaskets on water pumps were generally coated with a product that was thin, but helped seal.

I wouldn't trust those sorts of details in a DIY article by an anonymous person on the web, unless I knew it was written by a trained technician.

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2007 X3 3.0si, 6 MT, Premium, White

Retired:
2008 535i, 6 MT, M Sport, Premium, Space Grey
2003 X5 3.0 Steptronic, Premium, Titanium Silver
2002 325xi 5 MT, Steel Grey
2004 Z4 3.0 Premium, Sport, SMG, Maldives Blue