Another hint that I do, is I pick off all of the sepals from the rose, so there is nothing to distract my flower. Use a tripod, with the remote trigger, and go in close. I shoot in aperture priority, and have some shots as long as 30-45 seconds...so you definately NEED to have a tripod. don't get discouraged...I think I must have taken about 2000 shots before I ever got some consistently where I liked them
Another bit of advice , which I got from Brad Towery. Start at the lowest f stop, and continue shooting the subject at every f stop your lens has. It won't take long for you to see where you like most of your shots. (I used to start at f 2.8 and go all the way to the end.....now I start at about f 8, and go to about f 11. give or take.... this way I have several different exposures of the same shot.
One other thing when I first started, I would set up a shot, and then take every photo...upload them to the computer first, before moving it.
Over yonder, there is a photo in my gallery about set up....so you may want to have a look.
My advice is they are improving with each shot, but keep practicing. I am still far from the expert, but atleast I feel confident enough now to tell someone how to go about it