1. When lying on my back with my head on the water pillow, I placed my hands by my sides, with palms next to sides of the body/palms facing inwards towards the sides of the body. This was the most effective way to position the hands, for me, at least.
In other words, hands positioned the same way as when you stand with hands by your sides. Palms next to the body.
I tried lying with palms up, then palms down, then palms facing inwards to the body. I found that the best position was palms facing in to the sides of the body/palms placed alongside the body.
Hope I've explained that clearly.
2. I bought a new wine cask approx. every 6 months, emptied out about half of the wine, and used the half-full bladder as a water pillow.
If I forgot to buy a new water pillow regularly, I found that the therapy stopped working. Or that lying on the much-used water pillow made my symptoms worse.
I deduced that it is necessary to replace the water pillow approx. every 6 months, if using it every day.
3. I experimented with varying amounts of liquid in the water pillow. I think the amount of liquid needed can depend on the the size of the person's head.
Too much liquid: it's hard to keep the head on the pillow; the head rolls off the pillow.
Too little liquid: the head sinks right through to the surface below the water pillow, and no benefits are attained from lying on the water pillow.
4. I have seen "water pillows" for sale on Amazon. I do not know what these are, or if they would give the same results I achieved myself, for much less expenditure.
I would advise anybody who tries this therapy to purchase a wine cask (a box of wine) at little cost, and try the bladder half full of wine, as a first water pillow with which to experiment. Don't spend lots of money on gadgets or devices. It might be money wasted.
If you do try this therapy, please report your results here on this thread, or send me a PM. Thanks!