Goals 

The goals of most S&S characters are pretty basic and often pretty coarse compared to those of many epic fantasy characters. They want money, sex, booze and power either temporal or mystical. Revenge is always a good motivator as well. They are usually quite uninhibited about how they achieve their goals as well. You should keep this in mind when designing characters and scenarios.

Villains 

The classic sword and sorcery villain is the scheming sorcerer. He or she is usually a power behind the throne figure. They use their magic to dispatch their enemies and advance their goals. You can never go far wrong by giving the heroes an enemy like this and have that enemy do something terrible to them-slay their family, torture them, betray them and take all their money, be a rival for political power or the favours of the beautiful scheming princess. Having a villain whom all the heroes hate for their own distinctive reason is a good way of binding together an adventuring party that would normally only be motivated by self interest.

Politics 

Politics has a big role in many S&S tales. Factions of nobles scheme at a king’s court. Mercenary generals seek favour or plot to seize power. Rivals must be assassinated or discredited. PCs should find themselves drawn into these conflicts from time to time sometimes as ignorant catspaws, sometimes as willing henchmen, sometimes even as instigators. In general the motives of most people tend to be far more mundane than in high fantasy or classic D&D. They are out for personal gain, or revenge, or to remove their rivals. Usually even those who are involved with powerful evil sorcerers see them only as a tool to be discarded when the job is done. Naturally the sorcerers tend to see themselves as something more than that. Generally speaking you can’t go far wrong in an S&S campaign if you draw the players into a web of intrigue.

Monsters 

Monsters are everywhere in S&S worlds. They usually seem to favour out of the way locations from which they rarely emerge to trouble the rest of the world. Woe betide any intruder into their territory. A particular favourite of the genre is the last degenerate survivor of a dying race who is worshipped as a god by some particularly decadent humans, or kept bound by a particularly fearsome sorcerer. This is a very good way to introduce a powerful monster into a campaign, and even allow them to be found right in the heart of a city. Who knows what the thing is that stalks the tunnels below the Temple of Dark Shadows?


Customising a S&S campaign 

Obviously these rules are only the smallest of starts when it comes to discussing a S&S campaign. There are many possible options open to you and you are not limited to adapting published works. It is easy to imagine many different sorts of worlds. Imagine one where divine magic is white magic and does not cause taint, and arcane magic is black magic and does. In such a world a sorcerer who restricts himself to spells from the cleric list need never suffer taint. 

You could also introduce more classes from the CRI. As long as their magic causes them fatigue, they should be fairly balanced compared to the existing classes although I make no guarantees, not having tested any of them. 

You could also introduce more races. I think that using these rules you might actually end up with something closer to most published epic fantasy than you would get using the core rulebooks. However, this is the subject for another rule set entirely.