There are two modes for ratification: legislature or convention. The Twenty-First Amendment, repealing the Eighteenth Amendment, was by convention.
Ratification by the legislature is by resolution. If a majority of each of the state's legislative chambers votes in favor, the amendment is ratified.
Ratification by convention requires additional steps.
In the case of Massachusetts, for the Twenty-First Amendment, a resolution was passed on April 20, 1933, creating forty-five districts for the election of delegates from among three candidates per district. The candidates were selected by government officials, including the governor, lieutenant governor, etc.
On the ballots, each candidate's name was followed by an indication of whether they were for or against repeal. The people voted. The delegates met in convention.
Ratification of an amendment by convention, never having been done before, different states chose different means for holding the convention.
The principal difference in procedure lay in the selection or omission
of various committees. Some of the conventions-for example, in Arizona,
Colorado, Delaware, Florida, Idaho, Illinois, Indiana, Iowa, Kentucky,
Michigan, Missouri, New Jersey, New York, Pennsylvania, Texas, and
Utah-appointed committees. Others did not. When a motion was made
in the Massachusetts convention to authorize the chairman to appoint
committees on rules, elections, and resolutions, Delegate Charles F. Ely
demurred on the ground that the delegates knew they had been elected
and for what purpose. He said he failed to see why it was necessary to
have the committees at all. There being no opposition, the committees
were dispensed with and the delegates without debate voted to ratify
the proposed amendment.
The final vote was 45-0 for ratification.