Akatsuki's Plan

The Akatsuki's Plan is based around the use of all of the demons known in the Naruto Universe. There are several phases that must be completed in order for the scheme to be a success.

Phase I
The first part is to gather the necessary supplies to continue their operations. This includes money, equipment, etc. Also, during this phase, the Akatsuki members are assigned demons in which they must capture and bring to a secret base to extract from the jinchuuriki. The Akatsuki is currently stuck on this phase, since Naruto still holds the Demon Fox.

Phase II
Their second phase involves the release of all of the demons they have captured, setting them against the Five Great Shinobi Nations. Once these villages fall, the Akatsuki would come out and recapture the demons, completing missions normally reserved for the great nations. This would eventually lead to the bankruptcy of the lesser ninja villages, and force them out of business.

Phase III
When the villages are all bankrupt or destroyed, the only thing left to do is control the demons in captivity. At this stage, the Akatsuki would be the only ninja group that has the resources to maintain itself. Therefore, the Akatsuki, essentially, would take over the world.