The guidelines to consider are recommended by the FundéRAE.
June 28 was established as the International LGBT Pride Dayin memory of the confrontations between some members of this community and the Stonewall police, in New York, in 1969.
Regarding this date, the Fundación del Español Urgente -FundéuRAE-, provided keys for knowing the writing of the acronyms and their meaning.
Note that the names of international days are capitalized in the relevant terms. Therefore, the proper spelling of this festivity is International LGTBI Pride Day, and that of its abbreviated mention, Pride Day or Pride, as antonomasia.
Lesbians, gays, transsexuals, bisexuals and intersex (LGTBI)
Abbreviations LGBTI, corresponding to this group, are written in capital letters and without points. On some occasions you can find extensions of that acronym that add other letters, such as A for asexual (LGTBIA). On the other hand, the order of the letters that make up this acronym can be altered based on different reasons (GLTBI, LTGBI…).
Gays, plural of gays
The plural of the term gay is application. It is formed by changing the y to i and adding an -s. When gay functions as an adjective, it agrees with the noun it qualifies, as in gay association, gay associations.
transgender and transsexual
Although in some contexts they are used interchangeably to refer to people whose gender identity does not correspond to the sex they were assigned at birth, in other transsexual it is applied only to those who, in addition, have begun a reassignment process through treatments such as hormones or surgery.
As a shortening of these words, the trans form is used and it is not necessary to highlight it with italics or quotation marks.
LGTB-phobia or LGTBI-phobia
These terms are written with a hyphen between the initials and the compositional element: LGTB-phobia or LGTBI-phobia, as collected in the Pan-Hispanic Dictionary of Legal Spanish of the language academies. The form elegetebe(i)fobia is also well formed in Spanish. Nouns such as lesbophobia, homophobia, transphobia and biphobia are built with this same suffix.
Rainbow, better than rainbow
It is recommended to write rainbow in a single word and with a tilde on the i, better than rainbow, in expressions such as rainbow flag, rainbow manifestation or rainbow league. Its plural is invariable, rainbow, although if we use the rainbow form its plural is rainbows.