I'll throw my 2 cents in -- it's worth about 1/2 a cent!

There are, quite generally, several common types of gasket materials or situations where we need to seal against fluids ending up somewhere they shouldn't.

1) Paper gaskets -- these abound. They are designed to provide a proper seal installed dry. This of course assumes that both mating surfaces are clean and true/flat. Trying to make up for a lack of cleanliness or for surfaces that aren't true or are warped with the ubiquitous "RTV" sometimes works, sometimes doesn't, sometimes works at first and then begins to "doesn't" with the passage of time. I prefer to coat paper gaskets with Hylomar Blue -- it's a gasket dressing that primarily aids with dis-assembly. In terms of getting the gasket to stay where it's supposed to stay - many use adhesives of one type or another. Not my preference.

I prefer to buy a couple of extra bolts of the same size at the local hardware store, cut the heads off, and slot them for a flat blade screw driver. I can put these into 2 or 3 locations to act as temporary dowels to hold the gasket in place, start a couple of the OEM fasteners, and then remove the 'dowels' and replace with the proper bolts. Gasket held in place and no adhesives used. And yes -- I have little baggies marked accordingly (header dowels Ford 5.0L, lower intake dowels Ford 5.0L, header dowels LS3, etc.) This counsel applies to all the other gasket types listed below - use a temp dowel to hold the gasket in alignment whenever you can.

The one exception I'll make with regard to RTV/paper gaskets is if I have a configuration where 3 surfaces come together in different planes -- best on I can think of is where the lower intake, the head and the timing cover converge on a 5.0L Ford. In an area like that, I'll add a small dab of RTV in that type of "corner" to help the gaskets do their job.

2) Rubber, viton, buna-N, o-rings, etc -- these should be installed onto clean, true/flat surfaces with a bit of something to lubricate them so they don't bind when you start tightening things. Some use vaseline, some use a bit of oil. I prefer my trusty tube of white grease or engine assembly lube. Doesn't take much - you just want them to be able to slide rather than bind. This also applies to metal/rubber composites where there's a metal substrate coated with a rubber-like material.

3) Graphite/composite gaskets -- more and more common, especially on exhaust manifolds. These should be installed clean and dry. The graphite IS the lube it requires to not bind. When these seal coolant passages as well as other passages simultaneously (as in the lower intake manifold of a 5.0L Ford) if you just can't help yourself you can put the lightest smear of RTV on both sides of the gasket around the openings that seal coolant passages. But I don't do that and have never had a problem with them leaking.

4) Cork -- I HATE cork gaskets. I've tried just about everything to get them to seal reliably over the long term. I guess it depends on how one defines "long term"..... The approach that seems to work the best, for me anyway, is to smear a light coating of grease (I use wheel bearing grease) all over the cork gasket before putting it into place. This lets it move a bit, helps tremendously with dis-assembly. And in my experience, if you have no other choice but to use a cork gasket, you'll be disassembling it at some point to replace the leaking cork gasket.

5) Threads -- Sometimes threads penetrate into coolant passages and the like. I use Permatex or ARP Thread Sealer. They're designed to not ever harden or leave debris behind when you remove the fastener in the future. I would NEVER use RTV to seal threads. It's not designed for that -- and clean up after disassembly becomes a real pain.

6) Bushings -- I usually lube these with Armor All if they're rubber (sway bar links, shock bushings, accessory bushings or shifter bushings, etc), and water resistant grease formulated for poly bushings.

Lastly - pet peeve - almost every non-cast, aftermarket exhaust manifold/header I've tried over the years has a head flange that isn't true. They're usually warped a bit from the welding. And I've watched lots of folks struggle with stripped threads (lucky if it's the bolt/stud, unlucky if it's the threads in the head) and bolts that keep backing out on their own -- all because they're trying to pull a warped manifold flange flat against the head with the header bolts. Check the header flange with a proper straight edge. It's it's not flat/true - spend a few bucks at the local machine shop and have them mill it flat and perpendicular to the fastener surfaces. It will bolt up perfectly, it'll seal, and the fasteners will stay tight.