Poetic or sung Mando'a is much more free-form and can be hard for non-Mandalorians to translate. Most poems and songs are embedded in culture, so all native Mando’a speakers understand the meanings. — Karen Traviss, "No Word for Hero: The Mandalorian Language," from Star Wars Insider 86
These grammar rules were deduced from the ones that Traviss shared or identified as Mandalorian. The rules are appropriate only for poems and songs that are trying to maintain a meter; do not do these in everyday speech, regular stories, or the like. For works that you share publicly, you should note the liberties that you are taking with the grammar to make other language enthusiasts aware of your deliberate choices.
Drop the entire verb ending when conjugating a verb (putting the verb in its active form) if you need to lose an extra syllable. Mark that with a beten (regardless of what was done in the original songs and poems), so the pedantic nerds don't think you can't conjugate.
Drop the command particle (ke) if you need to lose an extra syllable.
If one word ends with the same sound as the next word begins, drop the ending letter of the first word; be sure to mark this with a beten. For example: guuro orar (fond of thunder) can become guur' orar.
Use the articles (te, eyn, haar) or cuyi if you need an extra syllable or two.
When singing, add "ah" or "oh" sound after a consonant, like we hear kar'ta pronounced as "kah-roh-ta" or Taung as "taun-gah" in the songs. Note that there's no written cue for this extra syllable; include it with any other notes.
Translating is difficult enough without trying to rhyme. However, one simple way to get a rhyme is to change the end of the verb from one vowel to another, since the verb endings generally were assigned by sound rather than meaning. This is definitely one to note so that no one thinks it's a typo.
These "formal" grammar rules are potentially helpful in poems and songs:
Mando'a permits dropping pronouns if context provides enough clues to let others know who you are talking about.
Adjectives/adverbs (no spelling or pronunciation difference between these in Mando'a) can be used before or after nouns or verbs.
If you are using a song to practice grammar, follow the standard grammar rules as closely as you can, making notes to your future self (or others, if you share it) about any deviations. If you are following the “key-word soup” grammar of such traditional Mandalorian songs as Vode An, be sure to include the full story upon which it is based; if this story is also written in Mando’a, be certain to use correct spelling and grammar.
The Ba'jurir Mando'a Discord server has a channel devoted to words categorized by syllable and stress as per the original dictionary. This link goes to the explanation at beginning of this server channel; there is also a post with tops for getting the meter correct. You can find a link to join this server in the Project Shereshoy Archive and Oyu'baat servers; for links to those servers, visit the home (yaim) page of this site.
https://discord.com/channels/792811531674714162/823653603980869702/823654917059117116