I don't grow roses, but I have seen two methods for propagating them. My mom had an old fashioned vining rose of some type and she would simply take about 6 in. cuttings and put them in a jar of water. She kept the jar on the kitchen window sill that received partial sun. In a couple of weeks roots would form. I don't recall how long she waited, but when there were plenty of roots she would pot them up and give them to her gardening friends.
I've seen modern gardeners propagate roses by snipping the ends of cuttings at an angle and then coating the end with rooting hormone. The mix they used had perlite in it, maybe 50% or so, from the looks of it. I hope one of these methods works for you!