If the dough becomes sticky adjust the flour quantity and smear little oil while kneading.Try to mash the sweet potato completely but still if very small pieces of sweet potato are remaining in the dough, roll the poories slowly.If you want to use both all-purpose flour and whole wheat flour, then add them in equal quantities.If you use whole wheat flour for the dough, then it absorbs slightly more liquid content, so adjust the curd quantity.Sugar quantity can be adjusted depending on the sweetness of sweet potato.