Reading for one's self musn't be any more dangerous than having a reading otherwise.
A reading can impose a good deal of conditioning on you, where you may self-fulfill a bad omen. There are cases when any kind of pre-warning won't do you any good...
This is actually a very deep philosophical subject (involving destiny and what not), however, strange as it may sound since I say this in a Tarot forum, I would not recommend this practice to someone I really care for. (Let's say my daughter, otherwise it's really none of my business.)
My highest aim in life is to be in such a point where I don't even feel the need for a reading, or any kind of oracle; since that point feels way better. I am not always there and that's all.
Don't get me wrong, working with the Tarot cards, doing readings and having the sight is a gift I appreciate a lot, and could even be a life style, a rewarding one, both for one's self and everybody else. I as rather a religious person see full dedication and surrender as a higher and more powerful point on behalf of myself.