I think you may be ok with stem cuttings taken in the summer, never tried to propagate these but would try this method myself. julien.

I would dip the fresh cut ends in warm water to stop the sap flow, then let them dry for a day or two before potting them up in grit and/or pumice, and letting them stand in warm shade. If the cuttings have many leave you will probably want to remove most, if not all of them, depending on the ambient humidity. Once they have roots--about 2-4 weeks later--they will start new growth, and can be re-planted into a gritty compost and hardened off. That looks like the variegated form, which will prefer afternoon shade, except in relatively cool, coastal areas. The amount of water it needs will depend on your local rainfall and humidity--it is considered to be moderately drought tolerant, and may need little to no watering near the coast. Inland, mountainous areas may get a little to cold in the winter for it to be happy. In containers, feeding needs to be regular, but doesn't have to be frequent--I would use a timed release at half of the recommended dose. In the ground, you will get better foliage color and bloom if fed rose food, half a dose, once in the spring, and once in midsummer.
Hope all this helps, Carojsmit!