Prayer garments for non-Jews must not have the Tzitzit (special corner fringes) which are commanded for Israel as a sign of their covenant. Rabbi Yoel Schwarts recommends that our prayer garments incorporate some reminder of the Rainbow Covenant. Whether it is in the form of a robe, scarf, or shawl wear it in the spirit of reverence and humility. Unless, one is sitting at a meal, one who is able to do so stands during prayer. -- ''Rabbi Yoel Schwartz, Oklahoma B’nai Noah Society DRAFT Rosh Hashanah prayer book''
