Police say he killed Ms Farrall, dumped her body, and fled to the West Coast where he picked up two hitchhikers and then attacked them.
He was granted name suppression and was remanded to the High Court in Christchurch later this month at a special court sitting at his hospital bedside today. He is undergoing surgery for dog bite injuries sustained during his arrest after a five-hour stand-off with police.
Ms Farrall's friends and family are struggling to come to terms with her tragic death.
Her partner of seven years told 3 News he was devastated.
Cory McKeown and a group of friends painted a colourful mural saying 'RIP Amy' on a fence at the supermarket carpark where her body was found, a few kilometres from her home, as a tribute to his 'beautiful' partner.
"There are no words for it," he said.
"She was my life, my rock, my soul mate."
Another friend, who did not wish to be named, told APNZ today: "She was always helping people. That was just the way she was. She's tried to help this guy, but ..."
Supermarket bosses gave permission for the mural to remain for a week after her friends approached them for permission.
They will be allowed to paint a tribute piece on the fence for the anniversary of her death every year and come and pay their respects, a supermarket spokesman said.
A large group congregated around the mural in afternoon sunshine today. They didn't want to comment further and wanted to "be left alone to grieve".
Earlier, Ms Farrall's family had issued a statement saying they were "devastated that her caring nature appears to have been tragically taken advantage of."
A memorial service was held outside her Wildberry St house in Woolston yesterday afternoon.
A poignant shrine with framed photographs and messages, along with bouquets of flowers, was placed on the fence.
Behind the wooden fence and police cordon, the tidy home is still being combed over by police forensic experts and guarded by constables.
Ms Farrall, a former Lincoln High School student, studied Mental Health Support Work at CPIT (Christchurch Polytechnic Institute of Technology).
She worked as a caregiver for Richmond Fellowship in Christchurch, a national non-government organisation that provides community-based mental health and disability support services.
Watch: Homicide investigation launched
Police confirmed yesterday that the 38-year-old man from Otaki, on the Kapiti Coast, had lived with her at her Wildberry St address for a short period before her death.
One friend, Evie Penney says she's "absolutely devastated" to lose her best friend so suddenly.
"You are a truly loving soul and the kindest person I have or will ever know," she wrote on Facebook.
"No words can describe the pain and disbelief we're all feeling right now."
Hayley Mitchell paid tribute to the "best role model a little cousin could ask for".
"There will forever be a hole in our family that nothing will be able to fill."
