IPA: /ˌʌnprɪˈtɛnʃəsli/
KK: /ʌnprɪˈtɛnʃəsli/
In a way that is simple and genuine, without trying to impress others.
She spoke unpretentiously, sharing her thoughts without any showiness.
Unpretentiously → It is formed from "un-" (meaning not), "pretentious" (from Latin "praetendere", meaning to stretch forth or claim), and "-ly" (meaning in a manner of). The word describes a manner of being that is not claiming or stretching forth to show off, hence, modestly or simply.
Think of 'not' ('un-') being 'showy' ('pretentious') — so unpretentiously means acting in a modest or simple way.