Washington (CNN) President Donald Trump rises around 5:30 a.m. and begins making his first calls to aides and lawmakers as early as 6. He's dressed in his signature dark suit by 8 a.m. at the latest, White House sources told CNN, and although he doesn't drink coffee, his proclivity for Diet Coke is widely known.

Dr. Ronny Jackson, the White House physician who conducted the President's first official physical evaluation last week, offered the nation new insights into Trump's health and daily routine Tuesday

Among them: His days begin early, after only about four or five hours of sleep, and Jackson advised the 71-year-old, 239-pound Trump to lose 10 to 15 pounds in the coming year and develop a regular fitness routine.

For now, the President's routine seems focused mostly on upending Washington . Current and former White House staffers, advisers and allies describe a restless President who sees his private residence as his real Oval Office and makes many key decisions each day before his official schedule gets underway.

"As we have said before he often has calls to foreign leaders, Cabinet officials, lawmakers and senior staff during this time," White House press secretary Sarah Sanders told CNN.

Though his predecessors often arrived in the Oval Office by 9 a.m., Trump prefers to start his day where he feels the most comfortable and unfettered -- inside of the private residence. Aides and allies say the President likes spending his mornings there because it affords a greater sense of normalcy than the Oval Office, which was once abuzz with unannounced visitors, but is more restrained and structured now that chief of staff John Kelly runs the West Wing. In essence, the President -- who once referred to the West Wing as "a dump" before it underwent a series of renovations in August -- sees the residence as his real Oval Office.

The morning

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Once he is up, Trump spends most of his morning in the Yellow Oval Room on the second floor of the White House residence, with his Twitter-enabled cellphone in one hand and the White House landline in the other. He is surrounded by the front pages of The New York Times, The Washington Post, The Wall Street Journal and the Washington Times. He skims the headlines as "Fox and Friends" plays in the background for the next three hours.

Trump isn't the first President to convert the Yellow Oval into his personal study. Franklin Delano Roosevelt also used it as his workplace, and it is where he learned of the Japanese attack on Pearl Harbor, according to the website of the White House Museum

Only a select group of staffers visit Trump during his mornings in the Yellow Oval, and, even then, it is only because they are personally summoned by him: Kelly, top aides Dina Powell, Jared Kushner, Ivanka Trump and communications director Hope Hicks. National security adviser H.R. McMaster sometimes joins Trump in the residence if he is scheduled to make a phone call to a foreign leader during what has been dubbed "executive time."

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As the day nears noon, the President finishes up his time in the residence and strides over to the West Wing for a day of meetings, briefings and phone calls.

Most of the televisions in the West Wing are multiscreen systems, allowing aides to keep an eye on several news channels at once, but Trump chooses to watch one channel at a time. His Twitter feed is often a clear indication of what he is watching as he taps away on the screen in front of him, posting tweets that often replicate Fox News chyrons and tagging guests who made a point he liked on air while denigrating those who didn't.

It was this same routine that sent Washington into a tailspin last week when, less than 12 hours after press secretary Sarah Sanders issued a statement saying the administration was in favor of Congress reauthorizing a section of the Foreign Intelligence Surveillance Act, Trump contradicted his spokeswoman with a single tweet.

"House votes on controversial FISA ACT today." This is the act that may have been used, with the help of the discredited and phony Dossier, to so badly surveil and abuse the Trump Campaign by the previous administration and others? — Donald J. Trump (@realDonaldTrump) January 11, 2018

Minutes after a segment aired on "Fox and Friends" where Judge Andrew Napolitano urged Trump to not support the measure, Trump tweeted the exact on-screen graphic -- "House votes on controversial FISA act today" -- and sent Republicans who had been working to secure votes for the bill into a tizzy. After a phone call from House Speaker Paul Ryan explaining the issue, and why the tweet was problematic, Trump backtracked.

The phones

The President has multiple cellphones, which senior aides have privately but jocularly referred to as "Trump One" and "Trump Two," but he prefers to make calls from the landline and through the White House switchboard in the morning.

Who he calls largely depends on the time of day. His mornings are typically reserved for staffers and lawmakers, who he sometimes calls immediately after they've appeared on cable news. Later, after he is animated by the day's news, Trump will ring up old friends, former staffers and cable news hosts to ask for advice or fume about the day's coverage. One of the President's outside advisers believes this is because Kelly has typically left the White House by 6 p.m., and Trump is once again free to do as he pleases.

In one of his attempts to instill order in the West Wing, Kelly began screening all of the President's incoming calls on the White House switchboard when he replaced Reince Priebus as the chief of staff late last summer, allowing him to make the ultimate decision of whether someone should have access to the President. This has, at times, miffed a President who relishes his phone access.

It was at night, after his heated immigration meeting with a group of bipartisan lawmakers where the President reportedly made disparaging remarks about African countries and Haiti -- offering praise to Norway -- that Trump spent time phoning aides, allies and friends, asking them how they thought the remark was playing out in the media.