See that the President the Cabinet and staff are informed. If cut out of the information flow their decisions may be poor not made or not confidently or persuasively implemented.
Don't necessarily avoid sharp edges. Occasionally they are necessary to leadership.
Don't be a bottleneck. If a matter is not a decision for the President, or you delegate it. Force responsibility down and out. Find problem areas add structure and delegate. The pressure is to do the reverse. Resist it.
Be precise. A lack of precision is dangerous when the margin of error is small.