In order to be famous, it’s no longer enough to just be famous.

You can win a gold medal at the Olympics or have a platinum-selling album, but these days, you also have to be — cringe with us here — a brand. That means endorsement deals, Twitter followers, maybe even serving as spokesperson for a flavored water. A scandal or two usually doesn’t hurt.

But what can help set apart the sorta famous from the very famous is the celebrity reality show, or “docu-series” if you’re feeling fancy. These behind-the-scenes peeks at stars’ lives simultaneously keep them in the spotlight while bringing them down to earth, and (they hope) gain them millions of new fans. It’s a difficult line to walk, and some series can come off as desperate and fake. If it’s done well, though, it can catapult lower-tier celebs to fame that lasts for years.

This week marks the debut of two such shows. Sunday, E! sets in motion “What Would Ryan Lochte Do?,” a look at the Olympic swimmer who made headlines at last year’s London games — not so much for his victories and friendly rivalry with teammate Michael Phelps as for a flurry of awkward interviews and self-deluded sound bites (trademarking the frat-thusiastic phrase “Jeah!”) that gave him a party-boy reputation.

On Tuesday, MTV premieres “Ke$ha: My Crazy Beautiful Life,” which follows the pop star who shot to fame after the release of her 2009 mega-hit “Tik Tok,” on which she sang about brushing her teeth with Jack Daniels. A few million album sales later, the singer — born Kesha Sebert — become known for her dance-rap anthems, being covered in glitter and embracing weird for the sake of weird.

Looking at the stars of both series, it’s easy to see similarities: two people talented in their respective fields, with outlandish public personas that threaten to overshadow their achievements. There’s a lot to gain from so much personal exposure, and even more to lose. Whether or not the shows are good is almost irrelevant (both fall in the category of “entertaining in an aggressively mediocre way”). More important, both serve as warnings — or guides — to stars wanting to kick their fame up to the next level. What are the most important lessons to take away from the “celeb docu-series” genre?

These people are famous for having a skill. You need to remind people of that fact.

“How many medals do you have?” an off-screen producer is heard asking Lochte, who sits for his on-camera interviews wearing a bulky hoodie and blank expression, one of the few scenes that isn’t a gratuitously shirtless shot. Lochte sighs. “I don’t even remember what I got at the Olympics,” he confesses.

An animated chalkboard pops up: Lochte’s had five gold, three silver and three bronze medals at the 2008 and 2012 Olympics (that equals 11, the graphic helpfully summarizes). He also holds four world records. The show doesn’t go into his accomplishments in the pool in great detail. Much is made of his training starting at 7 a.m. every day, since it’s a given that he partied hard the night before. “Tomorrow morning, be ready, be responsible,” his swim coach sternly tells him after Lochte mentions he’s going out for “a couple beers.”

“My Crazy Beautiful Life,” however, focuses much more on Ke$ha’s career, particularly what happens on stage. There are the obligatory shots of her trademark eye-searing set pieces and costumes — glitter guns, horse heads, neon glow-in-the-dark paint, sequins, lasers.

The series also shows what happens after the singer collapses backstage after performing, and it’s not glamorous. There’s gasping for breath, chugging water, and extreme makeup removal — and in one instance right before a huge show in Europe, she loses her voice.

As her manager explains that she needs to get lots of rest and sleep next to a humidifier, Ke$ha is on the verge of tears as she scrawls “I HATE THIS” on a piece of paper.

No, a lecture on proper use of a humidifier doesn’t scream rock-and-roll. But it’s an intriguing look at all the little details of celebrity, and the show is more interesting for including such scenes.

To make sure you aren’t labeled as an annoying overachiever, it’s important to develop a distinct public image. And for a reality show, it’s better if that image is “a crazy person.”

There’s a fascinating dichotomy between both stars’ skill sets and public images. Both are remarkably talented in areas that require a lot of work, but both find plenty of time to act rather strangely.

For Ke$ha, that means the aforementioned use of sparkles and absurd animal costumes, chugging bottles of vodka and having a much-discussed fixation on men with beards. “I want to find a man with a big beard who isn’t intimidated by my fierceness,” she proclaims.

Hobbies? Those appear to include some light stalking, specifically of her ex-boyfriend. She drags her friends into an adventure that includes driving past his house and scouring the neighborhood for clues about how he’s faring living with a new girl. “I’m going to literally throw up on myself,” she says, crouching down in a car.

Lochte, meanwhile, indulges in plenty of bro-time with his “Lochterage,” a circle of friends whose only job is to “turn it up, all the time.” Surrounded by this Lochterage, Lochte also wears a shirt with hashtag #LoctheNation as the gang gathers to play some flag football.

“Being Ryan Lochte is . . . fun,” he says. He even gives a long, detailed description of how he came up with his catchphrase “Jeah!” (Spoiler alert: It’s like the word “Yeah,” only with a “J.”)

Such spectacles, which show the subjects apparently completely removed from reality, may not make them seem like the most responsible people in charge of their personal brands. Still, it does make for somewhat entertaining train-wreck TV.

You must have a family element in your reality show to prove you are a real human.

At concerts, Ke$ha is usually slathered in neon body paint. At home, she’s just a regular 26-year-old in sweat pants.

And much of her show is a family affair. Brother Lagan directs the docu-series. Her mother, Pebe Sebert (a singer-songwriter herself), appears in several scenes, starting to sob as her daughter gets on a tour bus.

Crying, proud mom equals TV gold.

The Lochte family storms to the front and center of “What Would Ryan Lochte Do?” In addition to 28-year-old Lochte living with his younger brother, we see several Lochte family outings with his mom and sisters: bowling, movie night, dinner. These activities may seem contrived, but the arguing is all too real, especially about Lochte’s dating life.

The relationship between Lochte and his mom is rather adorable. In the second episode, they travel to the District for a charity event. After some mother-son bonding and a tour of the monuments, Lochte surprises his mom with a brand-new car as a thank-you for always selflessly supporting him. Naturally, she starts to weep with joy.

Write it down: Crying, proud moms equal TV gold.

Address how the media portrays you, be it tongue-in-cheek or in a fit of tearful rage.

There are two words for how the media sees Ryan Lochte: “Sex idiot.” That’s a direct title from “30 Rock,” in which Lochte guest-starred as a handsome, dim man who was used by women only for one specific reason. No one seemed to think this characterization was a stretch for Lochte to play.

Lochte doesn’t seem to mind this label. During his trip to Washington, there’s a particularly painful, obviously staged scene filmed at Local 16 restaurant on U Street in which a group of women grill him about politics, throwing around words like “Obamacare” and “legislation.” His eyes glaze over. “D.C. girls are straight to the point,” he says. “Politics, politics, politics, and more politics.”

That’s us.

Ke$ha, on the other hand, describes media coverage of her career with a healthy dose of anger, particularly aimed at celebrity blogger Perez Hilton.

“I was bullied in high school, sure, but that’s nothing on the kind of abuse I’ve taken from a particular blogger,” she seethes, as nasty headlines from Hilton’s Web site fly across the screen. “He single-handedly ruined the only relationship that ever meant anything to me.”

Ke$ha’s anger is more riveting than Lochte’s cool-tempered approach, but both offer a curious look at what it’s like to be chronicled by strangers every day.

You must make yourself as interesting as possible. But at the same time, you must seem like a cool, down-to-earth person overall.

Ke$ha talks about calling up her best friend when she needs cheering up. Lochte pranks his younger brother. Are stars really just like us?

Probably not. Yet the key to succeeding (as a long-term celebrity, anyway) is to have a camera crew follow you around and try to convince the world that that’s the case.

What Would Ryan Lochte Do?

(30 minutes) debuts Sunday at 10 p.m. on E!

Ke$ha: My Crazy Beautiful Life

(30 minutes) debuts Tuesday at 11 p.m. on MTV.