Some specific tips include to, first and foremost, plan your picture. Whether it's a macro (close-up) of a flower, or a field of wild flowers spanning across acres. For close-ups you will need to have a macro setting on your camera, or have macro lenses. I have a macro setting, which I used, but I also tried to get up very close to the flower since I have no special lenses yet. (If anyone has any suggestions on affordable macro lenses and filters that would be great!)
Secondly, the focus of the picture is very important. Decide on your focal point, or the part of the flower that you want to be in sharp focus. It could be a petal, stem, stamen or anything you want! Because this is a close-up, the focal point is very important!
Next, many sites recommend using a tripod for perfect pictures, but of course it is possible to do it without one.
In addition, trust your light meter, try for the best light and try to avoid distractions in the background....unless thats what you're going for. All in all, have fun experimenting and maybe you will get some good shots. That's what I tried to do, but after seeing all the amazing pictures of flowers in the link above....I think I have some more work to do :)