WordNet sense 1 (not having or showing or requiring special skill or proficiency):

unskilled

WordNet sense 2 ((of persons) lacking art or knowledge):

uncultivated, uncultured

WordNet sense 3 ((used of persons and their behavior) not refined; uncouth):

unrefined

WordNet sense 4 (openly straightforward and direct without reserve or secretiveness):

candid, open

WordNet sense 5 (characterized by an inability to mask your feelings; not devious):

ingenuous

WordNet sense 6 (free from guile):

guileless, honest