How did the group protest the Stamp Act?

In Boston, opposition moved from fiery rhetoric to inflamed violence, fanned by a secret organization known as the Loyall Nine. The clandestine group of artisans and shopkeepers printed pamphlets and signs protesting the tax and incited the mob that ransacked Oliver's house.

Why was the Stamp Act protested?

The Stamp Act was passed on March 22, 1765, leading to an uproar in the colonies over an issue that was to be a major cause of the Revolution: taxation without representation. ... Most Americans called for a boycott of British goods, and some organized attacks on the customhouses and homes of tax collectors.