Thank you!
For my Macro shots, I use the camera flash, with a diffuser ( called a "Puffer" ) this way I can shoot at a reasonable ISO, and have the shutter speed around 200 - 250. This helps me keep the images sharp. 99% of my macro shots are hand held when you see me using the 100mm "L" series lens. For some of my butterfly shots. I'll use my 600mm lens and shoot from a tripod. this gives me a bit more control over pic comp. I do try very hard to comp the pic in the view finder, and then fine tune it with my cropping. Use an F stop around 6-9, for your macro shots, this helps the backgrounds disappear and highlights the subject of your frame. Hope these tips help you out. If you need any other help, just note me, this is how I learned from some of the worlds best many years ago, and I'm just returning the favor they showed me.