My advice is to start in a yoga studio rather than at home: the energy you breathe in a yoga class is too beautiful and it is important that the teacher corrects you if you do not do good positions because you get hurt, especially in the back, it’s a moment.
If you are dynamic people, I recommend you start with Vinyasa yoga or Power Yoga: the sequences are always different and very dynamic. You will work a lot on a physical level, but you will learn to breathe, which is not negligible since we live in apnea. Slowly, when you enter the yogic mood you will also learn to appreciate slower yoga classes like Hatha yoga.
If you are not super sporty and want to tone up and relax, then I recommend you start with Hatha yoga: the positions are held longer so that you can learn them well. After a while, you can try to do more dynamic lessons like Vinyasa Yoga.
If you want a very intense practice and you need discipline because you always have your head going about his business, then try Ashtanga yoga: there is a fixed sequence that, at first, will be guided and that, at a later time, will allow you to practice on your own by going at your own pace. Ashtanga is pretty cool, but it really allows you to turn your brain off since you have to focus on the sequence.
Try at least one Yin yoga class. In Italy, it is rare to find them, but they are the most difficult! Difficult because the positions are held even for 5 minutes and are often positions that work on the hips, one of the places where we store all our emotions. And so, it could happen that, in the middle of the practice, between one breath and another, memories and tears emerge without you understanding the reason. You will feel lighter than ever, inside and out.
There are many other styles of yoga (Rocket, Dharma, Bikram, Iyengar, etc.) and I invite you to try them all if you have away, but what I think matters most is the teacher. Follow the person who gives you something, who makes you get in touch with yourself while you practice.
Try different Yoga studies until you find the teacher who makes you do that “click”: the transition from yoga as an exercise to yoga as a personal growth tool.
Don’t live it as if you were going to a gym class. Be respectful of those who practice with the heart and mind before the body: do not speak during a class, do not complain if you cannot take a position and think of yourself without looking at the neighbor who may have been practicing for years and is “better ” of you. In yoga there is no “good” or “less good”, indeed, who is “good” is someone who can feel a change within himself during practice, not someone who can do the vertical as if nothing had happened.
Get advice from some friend who has been practicing for some time and who talks to you about how beautiful yoga is and how much it has changed and not how sloppy it is to do this or that position.
Do not be discouraged if the first lesson will be too tiring or too “boring”. Try again! Get out of your comfort zone!
If you have just started and want to perfect your practice Martina Sergi and Martina Rando have just published a really well-done book called Smart Yoga. I recommend it!