Hollywood loves a good comeback story. Just look at Robert Downey Jr., who went from doing prison time and almost losing his promising career because of substance abuse issues to a remarkable rebound to the top of the game and a billion-dollar franchise in "Iron Man."

Following her release from a court-mandated 90-day rehab stint
 last week, many are wondering if, after years of legal and substance abuse issues, Lindsay Lohan is finally ready for her close-up again. If this time it's for real, MTV News asked some experts what steps Lohan should take to earn her way back at the box office and stay healthy doing it?

"The most important thing for Lindsay to do is focus on her sobriety," said veteran casting director Marci Liroff, who cast Lohan in "Freaky Friday" and "Mean Girls."

Take A Look At The Early Days Of Lindsay Lohan

"I don't think she should be concerned right now with what her next big movie is," she added. "It's really, really hard to stay sober and she has to want to focus on her sobriety."

Liroff, who said she has a personal investment and concern about Lohan's health and success due to her previous work with the former child star, said Hollywood and Lohan should both wait before throwing her fully back into the game. Lohan made her first tentative steps back on Monday night, when she hosted a well-received episode of the E! talk show "Chelsea Lately," where she poked fun at herself and 1D's Harry Styles
.

Looking healthy, bright-eyed and comfortable on the show that has often made her the butt of its jokes, Liroff said she was glad to see that Lohan was able to poke fun at herself. "She was funny and at ease and she seemed very connected and conscious of her situation through her self-deprecating humor, which showed she's taking responsibility for her actions," Liroff said.

Liroff cast Drew Barrymore in "E.T." before the child actress fell into her abuse issues (from which she later recovered), as well as Downey Jr. in "Gothika" after he was released form prison. "I felt it was the right time for him [Downey] because he had proven himself already [in 'The Singing Detective'] and he had shown he could be a professional and was on the path to sobriety," she said of Downey Jr. And while jumping right back into the thick of things might not be the best thing for Lohan, Liroff said keeping busy and being of service is also a great way to stay healthy.

"I was initially worried that the first thing she did within a week was to jump back and host 'Chelsea' and be interviewed by Oprah," she said of Lohan, who also has a new movie, "The Canyons,"
 in theaters now. "I hope she's keeping herself in safe places."

If an actor is able to stay sober, their success will come about naturally, according to Pax Prentiss, co-founder of the Passages Malibu treatment center. "Talent lives inside of these people, but what gets in the way is drugs and alcohol," said Prentiss, who was speaking in general terms and not with first-hand knowledge of Lohan's recent treatment program.

"And the biggest part of staying sober is identifying the conditions that cause them to use ... something is driving them to drugs and alcohol. It could be a dysfunctional family ... [so] in order to stay sober long term, they need to heal those conditions."

Prentiss also pointed to Downey Jr. as an example of someone who seemingly dealt with those underlying issues. He said if Lohan is willing to do the same, she could potentially have the same kind of renaissance as the "Iron Man" star.

Former Disney executive and author of the forthcoming book, "Confessions of a Casting Director" Jen Rudin agreed that the most important thing for Lohan to do at first is to get her personal life in order. "Then, she needs to be a professional actor on the set, first and foremost," she said. "She needs to a choose a role, get to the set and be phenomenal, prompt, get her lines down and get it back together in terms of her professional life."

The other key is to be a team player during filming and learn from your past mistakes. Rudin said once Lohan re-establishes that she can act professionally on set, her career can get back on track. "I think everybody deserves a second chance in show business," said Rudin. "But I'd definitely want to makes sure she's in good shape. I'd want to talk to her manager and get confirmation that she's feeling good and will show up on set and make us proud."

Hiring someone with a reputation for substance abuse issues is always a risky move and Rudin said that kind of notoriety isn't always the best kind of buzz for a movie, or the kind you're looking for. "You want to make sure it's positive buzz," she said, brushing aside the old saw that "all press is good press."

In addition to "Canyons," Lohan has signed on for an eight-episode docu-series for Oprah Winfrey's OWN network slated for 2014 and a sit-down interview
 scheduled to air later this month.

As for whether Lohan still has what it takes, Liroff said her talent is "undeniable" ... in the right hands. "She is very talented and very watchable and has tremendous instincts as an actress, but she needs a strong and talented director to guide her talents," she said, noting that Lohan's biggest success has come working with Mark Waters, who led her through both "Friday" and "Mean Girls."

"She's a good girl at heart and that's why it's so sad that she has this disease that makes it hard for her to succeed," Liroff said.