A person who writes or improvises décima is known as a decimista or decimero.
Given the flexible method of counting syllables in Spanish verse, where an "octosyllabic" line could easily have seven or nine syllables (as normally counted), in writing a décima in English it would seem not unreasonable to write in iambic pentameter (theoretically ten syllables), which comes more naturally to English verse.
The décima is a form of folk song especially popular in New Mexico, where it flourished during the nineteenth and the early part of the twentieth centuries. It was one of the most popular song forms in fifteenth-century Spain and has had a very strong presence in Mexico and Latin America, where it is still commonly heard. A décima refers to a ten-line stanza of poetry, and the song form generally consists of forty-four lines (an introductory four-verse stanza followed by four ten-line stanzas). The décima deals with a wide range of subject matter, including themes that are philosophical, religious, lyrical, and political. Humorous décimas typically would satirize an individual's weakness or foolish act. A decimero would frequently challenge the target of the satire or his/her defender to respond in kind with a décima, thereby setting up a song duel that tested the originality and wit of contending composers.
Some poetic competitions known as payadas consists on poets improvising décimas.