The Alexander Technique is one of the best self-help methods I know. In my view practising the Alexander Technique is an application of mindfulness; conscious thoughts are harnessed to improve posture and balance. There is no need to go anywhere special to practise it.
This particular application of mindfulness iincludes an understanding of how vertebrates move, with the head leading and the neck relaxed. Although, like me, your initial reason for taking lessons is likely to be physical pain especially back pain, you may also, like me, experience wider therapeutic benefits including improved breathing and digestion and reduced depression and nervousness. This is because applying the Alexander Techeque involves the whole self so that moving more efficiently, with less tension, also improves whole body functioning such as breathing
I’ve been teaching the Technique for over twenty years and in my experience everyone who wants to learn it, can benefit regardless of age or level of fitness. And like learning to ride a bike, the skills you learn are with you for life.