IPA: /ˌʌnəˈtræktɪvli/
KK: /ʌnəˈtræktɪvli/
In a way that is not pleasing or appealing to look at.
The room was decorated unattractively, with mismatched furniture and dull colors.
Unattractively → It is formed from "un-" (meaning not) and "attractive" (from Latin "attractivus", meaning drawing towards). The suffix "-ly" (meaning in a manner) indicates the manner of being not attractive. Thus, "unattractively" means in a manner that is not appealing or drawing attention.
Think of 'not' ('un-') and 'drawing towards' ('attractive') to remember that 'unattractively' means in a way that does not draw attention.