The Hand in the Sand/Quick guide

Sandy Hand
Items needed: A Beer
 * Talk to Bert in Yanille, in the house next to the POH Portal to get a Sandy hand. (Chat 2-2)
 * Talk to Guard captain in the Dragon Inn, South of Bert's House.
 * Ring the Bell at the Wizards' Guild, and talk to Zavistic Rarve, who will take the Hand.

Sandy the Slavedriver

 * Talk to Bert again for a Bert's rota.
 * Travel to Brimhaven and find Sandy in a small house south of Dead Man's Chest Inn.
 * Search Sandy's Desk to get: Sandy's rota.
 * Pickpocket Sandy until you get Sand.

Truth Serum
Items needed: 2 Vials, a Lantern lens, Redberries and White berries
 * Travel back to Yanille, Talk to Bert to receive A magic scroll.
 * Ring the Bell at the Wizards' Guild and talk to Zavistic Rarve again to receive a Magical orb.
 * Talk to Zavistic Rarve again. (Chat 4-1)
 * Talk to Betty for a Bottled water. (Chat 1)
 * Add Redberries, then White berries (in that order) to the Bottled water in order to get a Pink dye.
 * Dye the Lantern lens to get a Rose tinted lens.
 * Talk to Betty again. (Chat 1)
 * Go stand in the doorway and "use" the lens on the counter to get a Truth serum.
 * Talk to Betty one last time. (Chat 1)

Sandy Truth-Be-Told

 * Travel to Brimhaven and talk to Sandy again.
 * Select an option until you distract him, and use the Truth serum on Sandy's Coffee Mug.
 * Activate the Magical orb and talk to Sandy again. Be sure to click every option.

And Sandy said, "Drat-foiled again!"
Items needed: 5 Earth runes and a Bucket of sand
 * Travel to Yanille and Ring the Bell at the Wizards' Guild to talk to Zavistic Rarve.
 * Talk to Zavistic Rarve again to get a cut scene.
 * Travel to Entrana (Deposit combat items) and talk to Mazion at the sandpit to get a Wizard's head.
 * Travel to Yanille, Ring the Bell and talk to Zavistic Rarve.
 * Quest complete!

Rewards

 * 1 Quest point
 * 1,000 Thieving experience
 * 9,000 Crafting experience
 * Able to buy pink dye from Betty
 * A secret reward from Bert - He simply loves sand, and wasn't in the job for the money. He will ship 84 buckets of sand to your bank if you talk to him after the quest. This can be done once per day (UTC).