I've kind of developed my own method w/ bits and pieces from others, focused on the water. I just put them in a dome, no heat mat, no fancy mister and it works great, I get about 85-90% success rates consistently, in fact, they usually all take, though a couple might linger past 14 days.
try to take cuttings when your mother is getting dry, right before you water her. I have no scientific support, just experience implying it's efficacy (maybe a cut full of water and food won't work as hard to build roots as fast because it's satisfied?iunno) immediately place them in water and let them sit for at least a few minutes to prevent embolism, then scrape off the outer layer of the bottom inch of the stem that will be submerged in your medium, exposing the cambium to facilitate rapid rooting.
after scraping the stems, place cuttings in a strain labeled solo cup of ALOE water (explained below) with 1/4 strength nutes -ph 5.8-6.2 - with npk more like 2-2-2, or 2-3-2 for lower ppm, instead of standard 3-1-2 for veg - but definitely no more than 1/4 the ppm of your veg food. this will give plenty of phosphorus for rooting, if it's diluted low enough ppm not to cause harm. and the aloe is like magic, this post is gonna be long enough, I'll let you Google aloe and rooting cannabis for yourself. since I've started using it over a year ago with low strength, high phosphorus 6 ph water, I've had far better success rates and I don't even look at clonex or any other rooting hormones anymore. but the soaking step is possibly what made the biggest difference besides the aloe itself; I'm not sure what's going on but once I started soaking my cuttings in for a few days, my success rates skyrocketed. clearly there's a reason,I could guess, but I'm not going to pretend to know.
to clarify ALOE water:
mix 1/4 strength, high phosphorus nutes in a gallon jug of water, ph to around 6, THEN pour half a cup of this nute mix into a blender with a chunk of aloe that's at least as big as your index and middle finger combined (I have yet to discover an upper limit, I've used 3 times this much before with no I'll effects, but it seemed redundant) blend until the aloe is well dispersed and no longer chunky (there will probly still be chunks no matter what though), return aloe mix to the rest of the jug, and shake well before using it (and plan to use it within a few days, or aerate it) now you have clone water. there's chunks in it and it's thick, and your babies will love it. in fact you should try aloe at all stages of growth...
moving on. leave your cuttings in their labeled solo cup of aloe/nutrient water for 2-5 days or longer if your not in a hurry, changing the water every day or two, as it's stagnant. the longer I soak them seems to correlate to higher success rates, but keep in mind you're dragging out the process. if success rates are more important, soak them for 4 or 5 days. NOTE: you only need about an inch of aloe water in each cup, just enough to submerge the scraped parts of the cuttings.
now to set the clones.
I avoid rockwool and root plugs because you can scrape cloning solution off your cambium when forcing cuts into those little holes. instead, fill seed trays with straight coco and soak each seed tray with your aloe water. make sure the coco is saturated, you don't want to re-water until roots begin to show, because you can rinse away your rooting hormone(s). now, you can make as big of a hole as you need -unlike rockwool or root plugs - set your cuttings, and then tamp the coco in around the stem, rather than squeezing it in a hole and scraping off all your rooting gel. I suggest you use gel from the aloe leaf like clonex or rootek, it has rooting hormones which is why we're using it in the first place, it's natural, and it's far, far, far cheaper. if you don't do the above gel dipping step, then at least add another teaspoon or so of aloe/nute water after tamping clones in for good measure.
place in a dome and voila.
I see roots in as early as a week, usually by 12-16 days they all have roots growing through the bottom of the tray, which isn't as amazing as what some people claim, but it's no exaggeration, and I think some of them are full of shit. I certainly don't believe the guy saying he gets roots in 3-5 days, I've known dozens of seasoned growers and I've never heard of that. most growers I know can turn 2 ps per 1000 w no problem, but they still struggle with cloning and lose around a third of them every time and they can take 2-4 weeks from cut to transplant. A lot of people exaggerate their cloning success, don't let that affect your motivation. be patient and consistent and you'll find something that works for you.
also. DO NOT spray your clones with water, that's making them take longer to root, you want them to try and build roots to get water, not give it to them through the leaves. the humidity in the dome is enough moisture to fall back on.
aim for >90% and right around 80°F and I can't see your environment being the issue.
bon chance