Happy Homemade Sew Chic has a list of simple tools you need to sew these simple garments. You got your scissors, your seam ripper, your needles and pins.
And then you have your bodkins. Two bodkins. Sounds like something from Shakespeare. The book happily includes photos:
You got your big bodkin (#11) for inserting large elastics into casings, and your small bodkin (#12) for small elastics or ribbons.
I have no bodkins, certainly not two of them. What’s a resourceful cult member to do, but improvise! Actually, I have always used this method and it works just fine. Attach large quilter’s safety pins to each end of the elastic. Pin one end to one side of the casing, to keep it from sneaking its way into the casing prematurely. Then thread the other one through, inching it along by feel until it emerges from the other side. Then remove the pins, sew the two ends of the elastic together with many many zig-zag stitches, and you’re done. I imagine that a heavy metal bodkin might thread through the casing a bit more quickly, but it’s not that big a deal.