A "direct choice" to be queer is when a person consciously decides, "I want to be queer," and then becomes queer.
For further discussion of direct and free choices versus indirect and un-free choices, try "What is an 'indirect choice'?" and "The Process of Choosing: A Conversation Between Gayle Madwin and Frank Aqueno." Gayle Madwin made a direct and free choice to become queer, whereas Frank Aqueno arrived at his queerness through a process of indirect choices in which he was not always made aware of the full range of possibilities available.
You can also find a detailed description of Gayle's direct choice in Gayle's QueerByChoice Member Profile.