... "...dirty rags swimming in grey water"--Harry was scheduled to go to Stonewall High school and Aunt Petunia was dying some of Dudley's old clothes grey for Harry's new school uniform; " ...a bottle of some amber liquid "-- one of the things Hagrid began taking out of the pockets of his coat at the hut on the rock when he came to get Harry to help him get his things for his coming first school year at Hogwarts.
"Madam Malkin was a squat, smiling witch dressed all in mauve." Madam Malkin was owner of Madam Malkin's Robes for All Occasions in Diagon Alley (see wikipedia list of Harry Potter characters).
"Gilderoy Lockhart was striding toward them, his turquoise robes swirling behind him."
Gilderoy Lockhart: "Hardly any of you remembered that my favorite color is lilac."
"Stand back," said Lockhart who was rolling up his jade green sleeves."
"The ceiling was velvety black once more."
"Gilderoy Lockhart was walking onto the stage resplendent in robes of deep plum."
"The walls were all covered with large, lurid pink flowers. Worse still, heart-shaped confetti was falling from the pale blue ceiling.
"They didn't see another person until they reached the entrance hall when a tall wizard with long sweepingauburn hair and beard called to Riddle from the marble staircase."
"The Hufflepuffs, who played incanary yellow, were standing in a huddle having a last minute discussion of tactics."
"The stranger was a short, portly man with rumpled grey hair and an anxious expression. He was wearing a strange mixture of clothes, a pinstriped suit, a scarlet tie, a long black cloak, and pointed purple boots. Under his arm he carried alime green bowler."
"Two large trunks stood open on the floor. Robes, jade green, lilac,midnight blue had hastily folded into one of them."