I found an interesting way to do this and they come out beautiful...I don't yet have pictures, but I am making the cake on Oct 1st, and hopefully I will remember to post it.
I needed large ones so I bought the Jem Easy Rose Cutters in 3" & 1 1 4" I think... To make the flower part I roll out the fondant or gumpaste pretty thick and then cut with the cutter. I ruffle the edges of the cutout on my foam and then take my veiner and just drag over each petal to make the veins. Then I make sure I poke a hole with wire into the center of my flower. Then take a mini marshmallow, half it and stick it to the medium or large flower former and lay the flower upside down with the center on the marshmallow. Then carefully bend the outer portion of the petal backward so the petals take the correct shape.
To make the stamens I took my wire, made a hook then rolled some of my gumpaste into a shape that looks like a hibiscus stamen (fat on one end and thin on the other.) and wet and inserted hook about halfway into the thicker portion of the stamen. Then I took the Wilton yellow stamens and cut them really short and inserted them into the thin part of the stamen and let them dry for however long it takes. (I used a picture of a hibiscus to see how to do this)
When you are finally ready to assemble your flower (I had to wait 4 days for the flower part to dry hard enough not to break) take the wire with the stamen on it and insert into the flower part and then tape with flower tape or whatever that stuff is. =)
That's what I did. I also painted them with pearl and luster dust too and they came out great. Flower formers probably make the process alot easier but I don't have them nor do I have the money to buy enough to make the amount of flowers I need so I improvised with the marshmallows and flower formers. If anyone has an easier way to do any of this please share!! Although this way sounds complicated but it really doesn't take that much.
Hope that helps!