1) Dip the bottom 25% of the cutting into purple Clonex rooting gel (https://www.ebay.com/itm/Clonex-Rooting-Compound-Gel-15mL-100mL-250mL-1-Pint-cloning-clone-rooting/261221097209)
2) Place the cutting into a clear 16oz Rooting Cup that is filled with slightly damp HP Pro-Mix potting mix (or you could use 4x4x9 nursery pots, which are bigger and also work well). If you can squeeze any water out of a fistful of the potting mix, then it is too wet. You can add perlite or vermiculite to the potting mix in advance to help make it more fluffy/airy, but do not use any fertilizer at all.
3) Put the cups of cuttings into large clear totes like these from Wal-Mart (it's important to drill a couple of 1/4 inch holes into each end of the totes to increase airflow and minimize mold): https://www.walmart.com/ip/Ste
4) Put the totes near some well-lit windows (but not in direct sunlight) or in a room with some nice bright lights above it, and keep them warm. If I can't find a warm enough spot, I close them in a room and use a space heater to make sure the temp is in the low/mid 70's.
5) Maintain dampness (i.e. don't let them dry out). I have to lightly water mine about once a week, but it varies depending on the temperature/airflow conditions for each tub. Aim for watering them only enough to recreate the original dampness level.