The first pillar of Master of Orion is colony and production management.
Strong skills in managing the production of individual colonies is a lot of what separates the players capable of handling the Hard and Impossible difficulty levels rather than just the Easy and Medium difficulties.
In the lower difficulty levels, the computers do not get significant bonuses to their production and research and at the lowest levels they even get penalties across the board. In the higher levels, though, the AI gets massive advantages and it takes squeaking out greater than 90% efficiency on every planet every turn just to try to stay in the game, much less to try to win.
Being able to manage each area of planetary production and combine these areas across multiple planets to create a seamless "galactic economy" is key to winning the game. Your empire is not one planet. If it is, even on easy you have probably lost.
Galactic empires are made "for her pleasure" the bigger the better. Each planet also cannot be managed as its own individual entity. The combined production of all the planets must be managed as one big unit.
The worst way to go about the game is to try to divide the 100% slider bar into 5 categories evenly and put 20% in each category. If you try to do this, you will probably have difficulty winning the game - even on the easiest difficulty setting. This is just not an efficient way to manage production.
In order to learn how to best manage planetary production to eke out every possible edge and to give one's self the maximum chance to win, read on.