Get your manual out and learn about setting and customizing white balance. Learn and master selecting your focus. It looks to me like you are letting the cameras AF select where to focus, instead of selecting your focal point/points. This takes some practice. Don’t use clients. Get that focus nailed before any clients get in the mix (along with exposure, and color and a good grasp of how DOF works). Learn how to read histograms. Then study lighting. Work with still life first and work your way up to moving subjects. Learn how to push that iso up to acceptable levels in low light, and how to compensate without losing quaility. Once you get a good handle on these basics, then move on to posing. And never stop learning lighting and posing. Don’t take your book’s advice and go ahead and get on the Internet and study posing, and put what you learn into practice. When it’s time to market and sell again, Please do so honestly.
I’ll be spending the day doing exactly this. I knew where you were going with it. I understand thank you.