The procedure for creating new roses is lengthy and the success rate is very low, but if you are a really passionate about roses and you must make your own, it goes something like this.
You pick the two roses you want to combine, they have to be almost open, but not fully. With great care and making sure not to lose any of the pollen, snip the stamens from the first rose and store them in a bag.
Without touching the peduncle remove all the petals and snip the sepals around the stigmas of the second rose without allowing pollen to drop on the stigmas. Protect the prepared rose with a little paper hat until the next day. The following morning, using the stamens as little brushes, dab the pollen on the stigmas, keeping enough of it for subsequent pollinations. Repeat the process in the evening, then the following morning and the following evening. If you try more than one combination, label each one of the hips with the names of the parents and the date of the hybridization process.
Not all of the tries will take, but when they do the hips swell and ripen until the peduncle starts to dry out and turn brown, at which point the hip is ready for harvesting.
With a knife, slice the hips open and collect the seeds, which should be hard and woody and not float when placed in water. Allow them to dry, place them in a plastic bag with the lineage and the date of hybridization, place them at slightly lower than freezing temperatures and leave them overnight.
The seeds prepared as such can now be planted in starting trays. Plant a lot of them, only about a quarter will germinate, then proceed like you would with any seedling.
I tried this last year, unsuccessfully, but I’m not discouraged. You know what they say, “if at first you don’t succeed…”