Donald Trump and his allies are promising historic activity in the hours after he is sworn in, with a wave of executive orders to be signed this afternoon and more likely to follow in the days afterward.

The promises of "shock and awe" have steadily grown, with Trump first promising the total would be 100 early actions but that number steadily rising. By Sunday evening, it was up to 200 executive actions he said are on the docket.

During an inauguration eve rally in Washington, Trump said some of his advisors suggested spacing out orders over a series of weeks.

“Like hell we’re going to do it over weeks, we’re going to sign them at the beginning,” Trump said.

"We have to set our country on the proper course," he added.

For investors and business leaders set to try to sift through the flurry, it's already clear that certain sectors will be in keen focus.

Energy, for example, is set for a keen day-one focus with specific moves on the docket to open up drilling access and reverse Biden-era limitations on fossil fuel companies.

JIM WATSON via Getty Images

TikTok is also set to be on the day one agenda, with Trump promising Sunday that he would sign an extension to give the company a reprieve even as legal questions abound about whether he has the authority.

Trump is also promising surprises with a wide array of other issues that could also be addressed, from the federal workforce to crypto to student loans and more. Elon Musk and his Department of Government Efficiency (DOGE) could also be given some formal role in the wave of orders.

But many questions remain unanswered both about the orders and their impacts. Capital Economics, in a Monday note, pointed out "the only real certainty is that the path ahead in markets is likely to remain bumpy."

Overall, Trump’s primary focus Monday will be on immigration — with orders that could quickly lead to new enforcement actions in the US and on the southern border, even as immigration through Mexico has slowed over the last year.

There remains significant uncertainty surrounding the exact direction Trump will take on other topics — especially the issue of tariffs — but either way Trump is promising an intense flurry.

Read more: How do tariffs work, and who really pays them?

“You’re going to have a lot of fun watching television tomorrow,” the president-elect told the crowd Sunday evening at Capitol One Arena in Washington DC.

One financial area with some certainty: Energy

Trump is set to focus most on immigration in his initial actions, which could start new immigration raids immediately and also put a move to shut down the US-Mexico border in play.

Trump on Sunday promised it would be the beginning of his promised mass deportations, but with economic consequences that could be more gradual.

Not so much for another raft of orders teed up on energy.

Trump has promised a "drill, baby, drill" agenda to quickly empower energy companies that he is set to begin to implementing within hours. Trump also promised Sunday to use emergency powers to spur energy development to achieve the lowest electricity rate on earth and "double" the amount of energy produced in the US.

In addition, "there are a number of things that they can do on day one," Mike Sommers, the president of the American Petroleum Institute, offered in a call with reporters this week pointing to things like reversing Biden's pause on approvals of liquefied natural gas exports as well as rules around electric vehicles and tailpipe emissions.

Those priorities are top of mind and will be what Trump and his allies promise are a wave of actions to allow more traditional energy production in the US.

Trump is also expected to withdraw from the Paris Climate Accords, an international climate treaty that Trump withdrew from once before but Biden rejoined during his term.

One area of some uncertainty around energy is whether Trump can reverse Biden's move earlier this month to "permanently" protect more than 625 million acres of the US ocean from offshore drilling.

Trump has vowed to reverse it but questions remain about whether that's a day one move or one that takes a little longer.

"We believe that [Trump] does have the authority to reverse it on day one, and we will defend that position in court," said Sommers, who also noted this could also be an issue that ends up addressed by Congress.

The tariffs X factor

In November, Trump promised specific day one tariff action against Canada and Mexico, saying that on Jan. 20 "I will sign all necessary documents to charge Mexico and Canada a 25% Tariff on ALL products coming into the United States" because of his concerns about drugs and crime.

But whether he follows through — and whether the effects are immediate if he does — has been less clear of late.

The incoming Trump administration offered Fox News an early briefing on some of its plans and, perhaps tellingly, tariffs weren’t mentioned.

Either way, Trump is clearly aiming to go big but could roll those plans out more gradually at least in part not to spook markets.

The most muscular move for Trump, which remains under consideration, would be to immediately declare a national emergency using a 1977 law called the International Emergency Economic Powers Act (IEEPA).

That could even allow Trump to impose tariffs within hours but would also open the move to legal challenges.

At his confirmation hearing this week to be the new Treasury secretary, Scott Bessent underlined the ambitious plans as he defended sweeping tariffs and said that a plank of Trump's coming agenda will be "a more generalized tariff as a revenue raiser for the federal budget."

Crypto, TikTok and student loans

Of course, Trump and his team are also likely to unveil surprises, with a litany of other day one topics in the mix.

Amid a flurry of weekend drama over TikTok's fate in the US, the president-elect on Sunday said he planned to issue the tech company a reprieve when he takes office.

"I will issue an executive order on Monday to extend the period of time before the law’s prohibitions take effect, so that we can make a deal to protect our national security,” Trump posted. “The order will also confirm that there will be no liability for any company that helped keep TikTok from going dark before my order."

TikTok itself responded by coming back online and thanking Trump even as questions swirled about whether Trump could offer such assurances. 

In response to TikTok’s move, Senator Tom Cotton of Arkansas, the chair of the influential Senate intelligence committee, underlined that companies that help TikTok “could face hundreds of billions of dollars of ruinous liability under the law, not just from DOJ, but also under securities law, shareholder lawsuits, and state AGs."

JIM WATSON via Getty Images

Much of the day one focus for Trump will also be on the federal bureaucracy as he moves forward on long-promised plans to bring government workers — even traditionally nonpolitical ones — under his administration's more direct control.

Student loans could also be on the day one agenda as Trump had vowed to reverse many of Biden's moves toward forgiveness. But the shape remains unclear, with a debate about whether Congress should take up that issue instead.

Trump also alluded Sunday evening to his plan to pardoning his supporters who were convicted of their roles in the Jan. 6, 2021 attack on the US capitol.

"Tomorrow everybody in this very large arena will be very happy with my decision" on the rioters convicted for their roles that day, Trump said.

Trump will also surely use his renewed presidential powers to send a raft of his long-ago-announced nominees to the Senate.

Some are likely to then receive quick approval, like anticipated (for now) Treasury nominee Bessent who had a confirmation hearing this week that touched on tariffs and the Federal Reserve.

He is set for a final Senate Finance Committee vote on Tuesday followed by an expected quick confirmation on the Senate floor soon after that.

Ben Werschkul is Washington correspondent for Yahoo Finance.

Every Friday, Yahoo Finance's Rachelle Akuffo, Rick Newman, and Ben Werschkul bring you a unique look at how US policy and government affect your bottom line on Capitol Gains. Watch or listen to Capitol Gains on Apple Podcasts, Spotify, or wherever you find your favorite podcasts.

Click here for political news related to business and money policies that will shape tomorrow's stock prices

Read the latest financial and business news from Yahoo Finance