Those who do have experience seem to agree that opening yourself up to psychic abilities and/or spellcasting seems to also make you more noticeable to outside entities, which would make them more likely to find you. I haven’t had this experience myself though.

Most people seem to find as long as they take proper precautions, nothing negative seems to get in. For a psychic, this generally means shielding. For a spellcaster, this would be casting a protective circle before casting anything else. I feel as though they are essentially the same thing done different ways, but others disagree. I would say your best bet is to do as much research as you can to know as much as you can before trying anything. Then you can make an informed decision on if you want to try it out.

To answer your question, some of each, but pretty heavy on the side of study. I spent a long time studying magic and what it was supposed to be before I ever cast a spell. I learned about the idea of magic having unintended consequences during this study, and given how some could be very unpleasant, I decided it was always a good idea to be careful and specify that nothing harmful should happen to make a spell work. If that means the spell will fail, so be it. The number one intent is always no harm, because I would feel awful if a spell ever did any serious harm to anyone.

Study is also what introduced me to the Threefold Law and Karma. As I said, I don’t specifically believe in these concepts, though I do believe in the related concept of similar energies attracting each other. From my experience, this does seem to happen, though I couldn’t say for sure. Seems a fair number of people agree, but certainly not everyone.

As far as ethics in allowing people their free will and not hurting others, that’s pretty much my moral system and what I’ve come to think is the right way to do things over the course of my life. So it’s experience, what I’ve been taught, how I’ve been conditioned, everything that goes into making up someone’s moral system. Then just extrapolate that to magic. It should be noted that the Wiccan Rede does basically say the same thing, and many religions have similar moral ideas… some just get more complicated than others.

The idea of magic as a tool definitely came before me, but I have always felt that way from the time I began to think about it. It just made sense to me that way. It does make it easy to extrapolate morals to magic though.