After years of doing astanga, it took me a while to get used to Sivananda. The main differences for me were that you rested in between each posture, instead of doing a viniyasa (a mini sun salutation) to keep warm, and the sequence of postures was reversed. In astanga you start with the standing postures, then sitting and inversions (e.g. headstand and shoulderstand). In Sivananda the inverted postures are first, and the standing postures last. I’ve been told this is because the inversions put you in a more meditative state of mind, and by starting with them, you are inducing that state for the rest of the practice.
Also with Sivananda there should always be some pranayama (breathing techniques) at the beginning of the class. Most other types of yoga I’ve done have left this out. But in Sivananda it is a cornerstone, as it is supposed to lead to greater mental clarity. A yogi I knew once went on a pranayama course in the hope that he would gain insight into where he was going with his life.
At the moment my main practice is Sivananda. Every morning I do 5 minutes of sun salutations and then the 12 main postures (see above – note the clothing that you are suppose to wear, white for purity, yellow for learning ). Admittedly, I don’t do much resting in between postures (except after locust) so I can normally get through them in 20 minutes.
The most usual thing about Sivananda, which like me you don’t realise until you visit a centre or ashram, is that the organisation and most of the teacher training is run by Hindu monks or swamis. They have taken vows of poverty, so pretty much everything is done on a voluntary basis. It is also very religious, with idols, chanting and a strict adherence to vegetarianism (no drink, no coffee, no eggs and even no onions). Leggings and vest tops are out too — you’re supposed to dress modestly in baggy trousers and t-shirts.
The advantage of this type of yoga for me is that it’s a refreshing change from the materialistic world we live in. Also because the teachers are celibate monks and have completely devoted their lives to yoga, they know a lot about the subject, so the standard of teaching from the swamis is particularly high.