Regular layering - needs the right strain - I buy bushes that look like they can be layered, then I see if it develops roots and whether they are hardy and vigorous - requires trial and error.
A la George Mander - peat pots, promix/sand, rooting gel, monitor temp., mild fluorescent light, standard trays with 6" humididomes. cheers, Paul.

Depends what time of year it is. Inside under lights in fall/winter. Outside being misted in spring summer.

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;
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During the growing season:
Intermittent mist, 7 to 10 seconds on, 10 to 15 minutes off, depending on conditions.
Composted pine bark fines, with or without some peat and perlite mixed in (landscaping mix or soil conditioner).
The 3.5" pots the nurseries around here use for their annuals.
Hormodin #3 rooting hormone.

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

You guys use a mist system outside?

Mine's outside in the open air, hidden behind a hedge.