Anyone who the community feels has the gifts and commitment to read can be reader. One need not be a shapespeariang actor or a public speaker, in order to be a worship reader. There are many folks in your community that, with preparation and instruction can become faithful worship readers. Do not overlook children as readers. Many children are gifted readers and if their gifts are nurtured some of them will become effective lifetime readers or feel called to other leadership.
Most congregations choose their Readers badly.
Congregations that engage in this practive end up with readers who feel imposed upon and readers who can not prepare enough to be effective. Ultimately both the readers and the congregation suffer. Identify a group of persons with gifts for reading and set up a schedule. Give the readers preparation time and instruction. When Readers are supported many change from seeing reading as an obligation and begin to see it as a vocation and blessing.