The 15-year-old's body was found in a wooded area in the West Dunbartonshire town on 21 March. She had more than 140 injuries and been stabbed 61 times.
Paige was last seen entering a deli, owned by 32-year-old John Leathem.
He admitted her murder and claimed to have "panicked" after Paige threatened to report him for sexual assault after she applied for a job.
At the High Court in Glasgow, judge Lady Rae deferred sentence on Leathem until next month and told the married father-of-two: "This was a savage, frenzied attack on a child."
The court heard that Paige, who was 4ft 8in, had stayed with a friend in Clydebank the night before she was killed.
She had gone into the delicatessen, on Fleming Avenue, to buy a roll before travelling to a hairdressers where she worked in Kirkintilloch, about 12 miles away.
CCTV footage played in court showed Paige entering Delicious Deli at 08:21. Leathem is believed to have killed her shortly afterwards.
Prosecutor Iain McSporran told the court: "That was the last time she was seen or captured on CCTV alive by anyone other than by Leathem."
Just 10 minutes after Paige entered the deli, the shutter to the front door was pulled down.
Leathem told the owner of a nearby hairdresser who had peered in: "What a morning - the lassie didn't turn up. I had a nose bleed and I need to collect my car."
After collecting his car and parking it outside the deli, Leathem began his attempt to cover up the murder.
CCTV images showed him running to neighbouring shops to buy bin bags and anti-bacterial wipes.
Shortly afterwards he is seen taking Paige's body from the deli to his car.
Mr McSporran said: "The body of Paige Doherty was wrapped in what appeared to be black bin bags...her white socked foot protruding.
"He placed her body in the rear of the car and closed the boot."
Leathem went on to change his trousers and bought bottles of bleach before going back to his shop.
Mr McSporran told the court: "The shop then remained open for business with Leathem fully engaged in preparing food and serving customers until 3.15pm that afternoon."
Prosecutors believe he had initially moved Paige's body from his car to his garden shed.
Concerns were raised that night when no-one had heard from Paige. Her mother Pamela Munro went to police and a missing person inquiry began.
The day after the murder Leathem went on a family outing to Balmaha with his wife and young child.
On 21 March, two days after the murder, Leathem is believed to have moved Paige's body.
His car was filmed on CCTV at the area where her body was dumped - a wooded area close to the city's Great Western Road, less than a mile from the deli.
He then returned to the deli and opened for business.
At around noon that day, two people found Paige's body within undergrowth.
A post mortem examination later recorded 61 stab wounds, including 43 to her head and neck, and 85 further cuts - many of them described as "defensive in nature".
As police launched a murder inquiry, Paige's mother Pamela Munro wrote on Facebook: "We are absolutely devastated, as will many people who know her will be xxx."
Detectives later discovered that Paige had gone to the deli on 19 March "but had not walked away".
Leathem's shop, home and car were searched, after which he was detained.
Leathem initially denied any involvement with Paige's death but later admitted his guilt in the face of overwhelming evidence against him.
His lawyer told the court that Leathem had been a "normal and ordinary person" before the murder.
Ian Duguid QC, defending, said what happened was a "gross over-reaction" to a comment Paige allegedly made.
It was claimed the teenager had gone to the deli thinking Leathem may employ her, but that he told her he had other "candidates to interview".
Paige was then said to have told Leathem: "I thought I was getting the job. I will just say that you touched me."
Mr Duguid said Leathem suddenly stood up at this comment before Paige started screaming.
The advocate went on: "At that point, he reached across for a knife...he went to grab the knife and stabbed her."
Mr Duguid concluded: "It is not my position that the nature of the comment would mitigate the number of stab wounds or the brutality of the attack.
"I don't know if it is true or not, but I am only taking the instructions of the accused for what took place."
The QC added that Leathem had always "accepted responsibility" for the death.
The court also heard a number of victim impact statements from Paige's "heartbroken" family.
Her mother Pamela revealed how she continues to suffer "sleeplessness and nightmares".
Prosecutor Mr McSporran said: "She describes waking to hear her daughter's screams and the awful realisation that she was not there to help her."
Her husband Andrew Munro - Paige's step-father - was said to be "living in a state of depression".
The advocate depute added: "They cannot get out of their minds the terror they believe Paige must have experienced as the attack upon her began."
Mr McSporran added: "The effect on her siblings - and the loss suffered by her many friends - are all set out in touching detail."
Following the hearing, Det Supt Duncan Sloan, who led the inquiry, said CCTV footage had been "vital" to catching Leathem.
"Officers painstakingly reviewed hours of footage which ultimately revealed that Paige walked into that shop but didn't leave," he said.
"This, coupled with extensive forensic examinations of the crime scenes helped to establish what happened to Paige and who was responsible.
"I am sure that the sheer weight of this evidence has led to the guilty plea at court today."
The detective added: "Our thoughts remain with Paige's family, whose vibrant, bright young daughter has been cruelly taken away from them at just 15 years of age.
"Paige's whole future lay ahead of her and her life has been brutally cut short by the vicious actions of one man."
A man is facing a life sentence for the "frenzied" knife murder of Clydebank teenager Paige Doherty.