"To feel one's best" means to feel as healthy, happy, and confident as possible. It refers to being in a good physical and mental state, where one experiences a sense of well-being and satisfaction. Full definition
Confidence in dressing is about feeling good about what you are wearing and feel self - assured. (aprilwashere.com)
Regardless of whether your child is ready or not, any amount of sleep training won't go well if you don't feel good about what you are doing. (lullabyearth.com)
I committed myself to pursuing all that brings me joy and made feeling good in my body a top priority. (bodylovetribe.com)