This is a really practical source of advice for new, or more experienced, trainers. I had an earlier edition of David Leigh's book, and have used it to remind myself of all the angles I should think about when embarking on a training project.
There are plenty of titles around on the theory of the training cycle. This isn't one of them. It gives sound, hard-earned, practical tips that work. Dip into it when you need it, rather than read it cover to cover. There's a particular focus on skills involved in the delivery of training, with ideas on topics like building rapport, voice projection, handling stress and giving and receiving feedback.