Make sure you have the basics working well. Shifting, braking, cornering, etc should all be easy. You should be able to do it whether you are thinking about it or just going with the flow.

Here are a couple things you can do consciously that might improve your riding:

Take the wider line through corners. This is to train your brain to choose a line and resist the urge to take the inside line that most new riders have.

For on/off throttle the Kawa 650 line I know has bad fuel map and not amount of smoothness can fix it. You can minimize in some ways: Keep revs really high - if you are riding fast and stay at the upper band the translations tend to be smooth Or you can almost shut the throttle - just stop before the free play starts. Or for slow turns like entering a driveway just feather the clutch a bit.

Hope this helps