[Lily Bracegirdle]

Being a Ruling Steward would be basically like being a king. The role of the king ideally is to run the country: increasing prosperity, making sure everyone has enough to eat, making sure taxes are paid and treaties are made, keeping the borders intact, etc. It would be a full time job. No weekends for Stewards!

It may sound boring, but one of the things I think he would have done would be to go to a lot of meetings with his council and advisors, because he obviously can't do all those things by himself. Meetings about what, you ask?
1) Money. Governments need money in order to pay soldiers, build public works, etc. The Steward would have to decide how high to set taxes, taking into account expected expenditures (6000 new swords? Livery? Rebuilding the bridge in Osgiliath? More horses? More food for soldiers?) but also what the people could pay. (You can't expect 7000 bushels of wheat in taxes if there's been a drought, for example.) Linked with money is trade. Having a trade deficit means your country's money is going into some other country's coffers. If Gondor bought oranges from Harad and didn't export anything, pretty soon they'd be broke with a lot of orange peels sitting around. That's bad.

2) Security. The Steward needs to know about internal and external threats to his country. He'd have meetings with spies and scouts (assuming he wasn't doing it all by palantir) as well as with military advisors. What is Sauron doing? What's going on in Harad, or Rohan, or even Dol Amroth? Which of these things affect safety at home? Will the famine in Fornost lead to rioting? Denethor, being a bit of a paranoid guy, might also spy on his sons or other nobles to be sure they weren't going to try to depose him.

3) Diplomacy. The Steward would need to meet diplomats and make treaties and trade agreements. Most countries are not self-sufficient: they may grow food, but have no natural resources like iron, for example. In order to get what they need, even if it's pepper or silk, they gotta trade.

4) Justice. The Steward would need to write new laws and see they were carried out. Lawbreakers of sufficient rank would need to be judged by the Steward himself. The Steward would also mediate disputes between nobles.

When not in meetings, the Steward would probably do a lot of paperwork with his secretary, drafting letters telling people what to do, writing laws, ordering supplies for the city, etc.

Public appearances are also useful. Inspecting the troops to raise morale, visiting his allies to let them know he still cares about them, going to look at the new aqueduct to be sure the contractor isn't ripping him off, holding formal banquets, etc.

This is a short list of things I think a steward would be doing any given day of the week. In his off time he might hunt or pursue his other interests, but he'd be working most of the time. Also, while a Steward's son would be a military commander, the Steward himself would probably not be fighting on the front lines: he's too valuable to lose.

Cheers!
-Lily