In "Monkey Island 2," hero Guybrush Threepwood has to do a lot of revolting things in his quest to find the treasure of Big Whoop, but few of them are more disgusting than the spitting contest. Succeeding at the spitting contest requires careful preparation, precise timing and blatant cheating. Before you begin, you'll need to have collected the Ship's Horn from the shop on Booty Island, a Yellow Beard's Baby and a Blue Whale from The Bloody Lip in Woodtick, and a crazy straw from the same establishment.
Combine the Yellow Beard's Baby and the Blue Whale. Mixing these two drinks produces a new drink called a Phlegm and Tonic.
Head to Booty Island. The Spitting Contest is located on the far right side of the island. When you arrive, you'll see the Spitmaster, a row of spectators, and three flags marking the positions of the first-, second- and third-place spitters. Talk to the Spitmaster and tell him you want to compete.
Work your way down through the spitting dialogue options until you get to "Ptooie!" Guybrush will spit, but fall well short of first place.
Walk over to the flags on the right side of the spitting range. You need to move these in order to make the contest easier, but you can't do it with the Spitmaster and all the spectators watching you.
Blow the Ship's Horn. When the spectators and the Spitmaster hear the sound, they'll look to the left.
Pick up the flags. You don't need to select them individually; just pick up the blue flag and Guybrush will take all of them, moving them down the field one space.
Use the crazy straw on the green Phlegm and Tonic to drink it. Guybrush will remark that this drink makes his spit thicker.
Talk to the Spitmaster again. He will announce your return to the spitting contest.
Watch the spectators carefully. Look at the woman on the right end of the line; she's wearing a red sash around her waist. When the wind blows, the sash flaps in the breeze.
Select "Ptooie!" when the wind is blowing the woman's sash. Guybrush's saliva, helped by the following wind, will sail past the first-place marker. The Spitmaster will award you a commemorative plaque -- a board with a glob of spit on it.
The plaque itself isn't very useful, but it's worth a lot of money. Take it to The Booty Boutique to sell it for 6,000 pieces of eight.