Whisk the flours/starch and salt together. Put the mashed sweet potato in a large bowl and add half of the flour mixture. Lightly need it in with your hands, then add the other half and knead just until no flour streaks remain.
Pull it together into one ball - the mixture should not be too sticky. If it is, add another tablespoon of almond flour and another tablespoon tapioca starch.
Then flatten into a disc. Cut the disc into fours. Dust a clean surface with millet flour. Roll out each piece with your hands & fingers on the surface until you create a snake-like piece about 6 inches long, and 1/2 inch wide. Then with a knife cut individual gnocchi, about 1 inch long. (You don't want them to be too big or they won't cook through). Press the tines of your fork lightly into them to make the indents.
Repeat for each piece of dough. Coat the surface lightly with more of the flour mix just so it doesn't stick when you cut it.
In a medium pot of lightly boiling water, pour half of the gnocchi in. Wait until they begin to float to the top, then let cook for a minute or two. Remove with a slotted spoon and lay on a cutting board.
Repeat with the remaining gnocchi. Put gnocchi in the refrigerator for 5 minutes, then add 1 1/2 tablespoons olive oil to a skillet. Saute gnocchi for 5-6 minutes on medium heat, stirring, until they are crisp on the outside. Sprinkle with a bit of salt (this is key!).