A two day vigil began on Thursday and will continue until this afternoon with many more expected to sign the book of condolence.
His family will hold a private funeral later where they will say their final goodbyes, but at 11am his mother Jane has asked people to join in a "Thumbs Up For Stephen" event, and "do something to make others happy".
Millions of people across the world have been inspired by Stephen's courage facing terminal cancer.
And as his hearse arrived on Thursday evening, drawn by four white horses, there was spontaneous applause from the crowd. A bright yellow wreath bearing the icon of a smiley face lay beside the white coffin.
Leading the vigil the Dean of Lichfield, the Very Reverend Adrian Dorber, told the gathered mourners Stephen "in his all too brief life" had taught "how to make the unacceptable, beautiful".
"He chose to share his exuberance with us, not his pain. He was one of those very rare people who've helped us live our lives with generosity."
The teenager, from Staffordshire, had originally launched his fundraising appeal hoping to raise £10,000 for the Teenage Cancer Trust, but just hours before the vigil began the total had reached more than £4 million.
He died on May 14 after succumbing to multiple tumours.
The Teenage Cancer Trust's chief executive Siobhan Dunn has this to say:
