Unless you are the person (or people) who bought Tuesday’s winning Powerball ticket in Los Angeles County, stop reading. This article is not for you. If you don’t have in your possession a Powerball ticket with the numbers 10, 33, 41, 47 and 56, with another 10 as the Powerball, you probably don’t need advice on what do with a sudden $2 billion windfall.

But there’s always the next one. That’s the funny thing about lotteries. Even though the likelihood of ever winning is incredibly low — just one in 292.2 million this week — it’s fun to dream about what one might do with the money. (By comparison, National Geographic has estimated the odds of being killed by a shark at 1 in 3.7 million. You’re even more likely to be killed by a hornet, wasp or bee, according to the National Safety Council, which in the United States in 2020 put those chances at 1 in just 57,825.)

Still, fantasizing about what $2 billion might buy is a fun thought exercise. Maybe it’s a fleet of luxury cars you want, or a very tiny country. Or a respectable portfolio of low-risk index funds designed to financially sustain your family for years to come. We’ve all got dreams.

The pleasure of this exercise is probably why TikTok abounds with people offering advice about what to do should you find yourself in this incredibly rare position.

There is so much lottery content, in fact, that a certain type of TikTok viewer has become something of a running joke: a person who, despite never, or rarely, buying a lottery ticket, is now an armchair lottery expert, furiously taking notes for a situation in which they will never find themselves. If you’re still reading this, you may be one of them.

“Me watching this like I’m going to win when I haven’t even bought a ticket,” one commenter wrote on a recent video from Vivian Tu. Ms. Tu, a JPMorgan Chase trader turned financial content creator, is better known by the name of her business, Your Rich BFF. She has more than two million followers on TikTok.

Ms. Tu’s first piece of advice is simple. Take a breath, and tell no one. “Keep your mouth shut. Say nothing to nobody,” Ms. Tu, 28, said in an interview. “Reason being, you know, you may think you know someone, but when there’s $2 billion involved people can very much change their tune.”

Next up, get out your camera. You’re going to want lots of photos of the front and back of the ticket, to prove that you do, in fact, have the winning ticket in your hand. Ms. Tu also recommends scans of the ticket, preferably stored in different locations. Keep the ticket itself in a secure location, ideally locked in a safe, she said. And make sure you know how long you have to come forward and claim your money.

“You’re going to want to try and stay anonymous if at all possible,” Ms. Tu said. In some states, including California, lottery winners are required to disclose their identities. Meaning this particular advice is not going to help this week’s winner or winners.

“If you’re in California and you are this lucky $2 billion Powerball winner, I would say change your phone number and delete all traces of you on the internet to have any sort of reference to where you live, what your community may be, and just really, really go out of your way to protect yourself,” Ms. Tu said.

If you can remain anonymous, that’s ideal, but options will vary from state to state. In New York, for example, lottery winners can claim their prizes under an an L.L.C. (limited liability company). In Wisconsin, you can’t be anonymous, but at least the state won’t make you appear at a news conference.

To decide how you claim, you’re going to need to contract a suite of experts, including lawyers and accountants, to help guide you based on whatever the rules are where you live. “I wouldn’t necessarily go with someone who markets themselves as a lottery lawyer,” said Haseeb Hussain, a lawyer in Chicago who has more than 400,000 TikTok followers. “I would try to find the best type of lawyer in the different types of industries that I would need when I come across such a windfall. Like, for example, a trust and estates attorney.”

Mr. Hussain cited Jason Kurland, a self-billed lottery lawyer who was convicted this summer after being accused of defrauding his clients out of $107 million, as a cautionary tale.

Mr. Hussain also recommended finding a real estate lawyer, a tax lawyer and a litigation defense lawyer. “If it becomes known that you are a lottery winner, people will try to sue you, just like people try to sue Will Smith, even though people have never met Will Smith, just because they know he has money and they come after it,” Mr. Hussain said.

A video that Mr. Hussain made offering his professional opinion on what to do after winning the lottery has been viewed more than 11 million times.

The advice these TikTokers are giving may be free, but some are capitalizing on users’ fascination.

Jackpocket, an app that allows users to play the lottery from their phones, reached out to Mr. Hussain about working together after the company saw some of his earlier TikTok videos about the lottery. In July, Mr. Hussain posted a video promoting the app. “Literally it took me a minute to make a video and they were paying over, like, four figures,” he said. “It was awesome.”

He added: “Hopefully I’m not encouraging gambling in any way, that wasn’t my intention. It really was to advise people what the best course of action is when you come across a windfall.”

If you’re planning to give money to friends or family, Ms. Tu suggested deciding early on just how much you’re going to give away. “If someone comes to you in a decade and says, ‘Hey, look, we want more money,’ you can be like, ‘Hey, I already put aside what I’m willing to give out. So that’s it. Period,’” she said.

You’re also going to need an accountant, Ms. Tu said. You and your accountant, or possibly accountants, will discuss how you’d like to receive your winnings: in a lump sum or a lottery annuity, which is smaller payments over time. (You’ll also discuss the significant taxes you’ll pay on said winnings, which will also vary based on where you live.)

“For the lump sum, go ahead and just guesstimate about 50 percent of the number that you’re seeing flashed big on the screen,” Ms. Tu said. “So this $2 billion winner assumes they’ll get $1 billion pretax. They then have to pay taxes on that lump sum number. So, again, go ahead and halve that. So even as $2 billion, winning is probably closer to like $500 million.” Forbes calculated that the California winner would take home $758.2 million after taxes with the lump sum option.

Deciding which option you’ll choose can require some self-reflection. “Technically, the lump sum is the smarter option,” Ms. Tu said, noting that interest made on relatively safe investments could earn more than the periodic payments. “But you should only choose the lump sum if, and only if, you know you have the self-control to spend, save and invest it wisely.”

But if you think you’re likely to squander your fortune, the annuity option may serve you better, “so even if you were stupid and blew your money the first few years, you would still have money coming,” she said. “Is the lump sum better? Yes. But, since human emotion is involved, would a lot of people also be better off taking installments? Sure.”

Ms. Tu added that she herself does not gamble, including buying lottery tickets. “When I was in high school, I had this math teacher who I really, really loved and he said something that always kind of stuck with me: ‘The lottery is just a tax on people who don’t know how to do math,’” she said.