Information from this page can found in "Cornell LGBTQ+ Resource Guide for Faculty and Staff", from Cornell University.
Incorporating a statement of inclusiveness for diverse identities into your syllabus acknowledges your support for these identities and sets an example for students enrolled in the course.
Example: I consider this classroom to be a place where you will be treated with respect, and I welcome individuals of all ages, backgrounds, beliefs, ethnicities, genders, gender identities, gender expressions, national origins, religious affiliations, sexual orientations, ability – and other visible and nonvisible differences. All members of this class are expected to contribute to a respectful, welcoming, and inclusive environment for every other member of the class.
It might also be helpful to include your pronouns in your contact information and provide LGBTQ+ specific resources for students, such as those found in this guide.