Slow down your rates on your yaw and roll, this will help to smooth things out a bit.
Do the same to the gimbal settings, same result.
Don’t do a lot of straight line flying connected by either a quick yaw or roll to one side, (normally caused by avoiding an obstacle). Watch Idaho Quadcopters on YouTube, he normally flys like that.
Practice doing figure of eights and circles in a park, so you can get used to turning one way then another.
Not bad for a first try, keep it up!