The last big thing to help sell an RPG campaign to your players is the story. You’ve got the characters — be it the buddy comedy team of your lawful evil fighter and lawful good paladin, the pulp-era absent minded scientist and the rough-and-ready pilot/adventurer, or your sex bot and her interstellar spy master; you’ve got the basic broad strokes of the universe — be it the sparkly vampire goth romance, the giant space empire versus the rebels, or the MTV cops fighting this weeks drug runner/spy/comedic vice peddler…

Now you need a kick ass first episode.

Unless you are doing a mystery series, use the KISS method: Keep It Simple, Stupid. Your interstellar spy master is trying to intercept the McGuffin from the bad guy, who is a notorious lecher…enter his sex bot (so to speak.) Find McGuffin, overcome an obstacle or two, the win or lose, but in the end the universe is sort of set up and maybe even a recurring bad guy.

Your post-apocalyptic world requires the characters to pull together against the zombies or robots of doom to try and get home/rescue their families/escape the contagion or war zone so that they can live to fight another day. You don’t need to know all the particulars of the zombie menace, or why the robots have turned on you. Shoot them in the head! Run for your life! But finish up with either a really good cliffhanger or a flight to (apparent) safety. Quick, straight-forward, all the flash comes from the actions of the characters.

Your lawful evil fighter and lawful good paladin come together (maybe with a few secondary characters for comic relief and magic firepower) to rescue a town from an evil goblin horde looking to steal food for the winter, or to save an important personage from capture, or to establish the will of the local lord over a rebellious band…their bad vs. good quips, but essential respect for the rule of the king/lord/law means they can work together (just this once!) in common cause. then conveniently, they’re needed again…and again. Maybe they lean to respect each others’ cultural differences and become friends.

But beside that — the story should be simple: get together, overcome obstacle, meet bad guy or privileged henchman, overcome obstacle to gain the McGuffin, overcome bad guys to escape/conquer/whatever. Keep the pace up and don’t let it bog down into an overplanning session. When in doubt, throw a chase, fight, or explosion into the mix. It works on the screen, it’ll work in the game.

Don’t be afraid to toss out any hints, subplots, or cool NPCs you created. The players will inevitably be drawn to the NPCs you thought were going to take off, or they’ll go in a direction in which your nifty characters are not going to be of use.