Great article in the Economist on how to build a religion. Excerpt:

At the outset, you must realise that success is unlikely if you go wholly against the grain of human nature. Granted, religion is all about forging the perfect man, or at least ensuring that, as far as possible, he lives up to divine expectations. But preternatural power has forged man in such a way that he will swallow some of your ideas about how to achieve this more easily than others.

By stressing the right ones, then, you can do to give a fillip to the painstaking process of perfecting mankind. This is what some temporal powers have been doing of late, when trying to nudge their citizens towards individual choices which are more socially desirable, with notable success. You can do the same. This will, however, require that you rein in your dislike for a moment and listen to what those ungodly scientists have to say, despite their unremitting efforts to explain away the need for your enterprise.

As in the case of states, your principal concern is to encourage co-operation among your flock. In the long run, groups that co-operate more have an advantage over those whose members are less willing to do so. This also means limiting the number of actual and potential shirkers. People, it seems, are naturally inclined to do this anyway, but you can egg them on with a few simple tricks.

First, you are better off plumping for a personal god, rather than some sort of indeterminate life force. Research shows that people who profess a belief in such a deity judge moral transgressions more harshly, which in turn tends to make them more willing to abide by the rules, and expend resources on enforcing them. This may be down to a conviction that they are being incessantly watched over by an attentive minder, who tallies their contributions (or lack thereof) and rewards (or punishments) in a cosmic ledger. Speaking of which, incorporating the idea of just deserts is a fine plan, too. Apparently, people are born with an intuition to that effect. Just remember to keep the misfortunes visited on wrongdoers commensurate with their misdeeds. Otherwise people will think it unfair and won't buy it. No fire and brimstone for littering, and suchlike.

More.