In words that end with a consonant, stress most often falls on the last syllable, with the following exceptions: The grammatical endings -n (for third-person-plural of verbs) and -s (whether for plural of nouns and adjectives or for second-person-singular of verbs) do not change the location of stress.
Preantepenultimate stress (stress on the fourth-to-last syllable) occurs rarely, only on verbs with clitic pronouns attached (guardándoselos 'saving them for him/her/them/you').