In an aquarium with an aerator?

In dirt in the shade?

In perlite, vermiculite, peat, sand or some other dirtish medium?

Air layering?

Rooting hormones?

Bottom heat?

All out hydroponic system?

Or something else?

coconut coir
clear pots
misting on 2 minutes off 10 minutes. Sunrise to 1 hour prior to sunset
Rhizopon AA #3 rooting hormone

In about 18 days, my HT cuttings look like this;

Dormant cuttings, including cuttings salvaged from the spring pruning discard pile:
The same rooting medium.
Two cuttings per pot in quart sized perennial pots.
I apply rooting hormone, stick the cuttings to about two thirds of their length, then place the uncovered pots in a wind protected area where they'll get morning sun only.

In my climate there's no need ever to root rose cuttings indoors, and no need to cover leafless cuttings in cool weather. We get plenty of rain in the winter and early spring. I root dormant cuttings in pots rather than in the ground so they can be safely potted up to gallons and moved to the pot ghetto for the summer. It can be difficult to pot up a young rooted cutting growing in the ground without killing it.

Pine bark fines are a dirt cheap and readily available commodity in my area, thanks to the regional tree farming industry. Coir works just as well, but not any better, and it's a LOT more expensive. I have to either drive to a larger city 35 miles away to get it or buy it online and pay shipping charges. Those of you who don't live in pine country and are having a difficult time finding a convenient source of coir might want to check out whatever is commonly sold as soil conditioner in your region. Others in this forum have reported high success rates with composted cotton seed hulls and composted Christmas trees.

A Penelope cutting rooted under mist