IPA: /ˈprɒp.ər.li/
KK: /ˈprɑːpərli/
In a way that is correct, suitable, or appropriate for a particular situation.
She completed the task properly, following all the instructions carefully.
Properly → It is formed from "proper" (from Latin "proprius", meaning one's own or particular) and "-ly" (a suffix used to form adverbs). The word "properly" means in a manner that is appropriate or suitable to a particular situation.
Think of something being 'one's own' ('proprius') and how doing it 'in a suitable way' ('-ly') means doing it properly.