There are a number of client concerns that you'll need to address when writing your blog. One way of approaching this is to write your posts as questions and answers. For example, "What causes dark circles and bags under your eyes?" Answer (and there's several): Age-related thinning of the skin, sinus congestion, allergic reactions, high-sodium diet, eye infections, tear duct dysfunction and hormonal changes. Solutions you offer can include the treatments you have in your spa for reducing dark circles.