Personally, I'm a fan of using A rubber gasket with sealant on the valve cover side to glue the gasket to the cover, then just using oil or grease on the head side. It makes the process of re-lashing the valves easier, because you don't have to worry about the gasket flopping around all over the place.

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Used to own:
'82 Dodge D150
Erson 270 Cam, O/S valves, mild port work, ~9.5:1 compression

Currently fighting with an '85 VW Cabriolet

My other passion

Gluing the gasket in place on either side just postpones the hassle from now until later. I don't recommend it. This is why there are tabs on the gasket and slots in the cover. If you engage all the tabs in the slots, the gasket won't flop. If you want to be extra-specially sure about it, engage all the tabs in their slots, then tie a loop of sewing thread through each bolt hole. The gasket won't go anywhere while you install it, and you won't be creating a glue hassle for yourself or the next guy.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Yes the glue turns a pleasant task into a messy and time consuming one. Any time you use glue or silicone it needs to be in moderation as well. Too much hanging inside the engine can break off and end up in the oiling system. Some silicones swell up with oil and become like a big snot in your oil that can squeeze past the oil filter and end up in the oil galleys. I'm not saying you don't need them, just use the right ones and do a clean job of it.

I like silicone on the valve cover gasket but I only put a small dime size drop between the bolt holes to hold it in place (I don't use it to seal the valve cover only to secure the gasket)