Very, very quietly
You mention only ethical and legal concerns, completely ignoring moral concerns, so my suggestions will be structured in the same way. One critical factor is the nature of one's ethics and the legal structure they submit to. The detection methods of the searching people/governments are also left ambiguous, making an answer even more difficult. The option of a protective client is also left unaddressed in the question.
LEGALITY
As legality is nothing more than a group of people saying it has to be a certain way, and has some method of backing up their laws (physical, social, or otherwise), your "legal" options will vary from country to country, and can be changed by simply moving. Some legal structures even ignore or refuse to acknowledge other legal structures as part of the laws.
ETHICS
The ethical strictures (ethics being defined for my purposes as inter-reactions concerning others, and moral as intra-reactions concerning one's self) will be potentially more restrictive. However, I will be unable to give detailed answers without some sort of idea of what ethical code your theoretical individual(s) would subscribe to.
After all, some ethical codes only require "good" treatment of a select group of individuals, while the same code permits pretty much anything to be done to "outsiders", up to and including theft, deception, and even murder. Some ethical codes also only require you to follow the legal code which applies to your own kind, and actively promotes ignoring the legal code of any other entity or organization. (Which is where morals start tying in, as well, but again, we are ignoring morals for this question).
Teleportation
This partly depends upon how exactly it functions. LoS-Range (Line of Sight-Range), Any-Mental-Visualization-Destination, Range-of-Leap, Atmospheric-Bubble-Effect, Risk-of-Material-Phase-Overlap, Self-Only versus Anything-Touching versus Anything-Seen versus Area-Affect, Living-Only or Non-Living-Only, Feedback-on-"Failure", Weight-and/or-Size-Limits, and so forth, all will change how this power could be used for profit.
This power could be difficult to use secretly, as there is usually a risk of observation at either departure or destination point. The risk increases if the tech level support remote monitors such as cameras, specialized lifeforms, robots, or sensors of various types.
If the individual can teleport objects without having to touch them, then this can be more profitable. Being able to remotely swap, add to, or remove the contents of a drawer, locker, safe, or storage unit has potential as a secure courier, as well as a thief, spy, or saboteur.
Super Speed
Again, exact parameters of the power become important. If the power quick enough to emulate a timestop, then it becomes very useful. Mid to high tech levels cause increasing levels of risk of exposure, however, even at such high speeds.
A career as a stage magician is a possibility, so long as the tech level doesn't support high-speed recording devices. Even if the speedy portions are hidden off-stage, you'd need to be careful of witnesses, planted or otherwise.
Super Strength
Possibly the most difficult to hide, unless your physique is non-obvious. Circus, Olympic, or Professional strongman would seem obvious fits, so long as control over the strength is very fine, and the individual can control their reactions so that they still react to situations as a 'normal' would, despite their strength. Bouncer or Bodyguard is also a possibility. If the strength is accompanied by toughness and resistance to damage, then exposure risks increases.
Mind Reading
Powers that have "no obvious effect" and are "not traceable" are going to be the best options for covert action of any kind. Remote Telekinesis, Clairvoyance, Clairaudience, Precognition, Psychometry, Danger Sense, Empathy, and all other such powers typically fall into this category along with Telepathy (mind reading).
Telepathy has a large number of possible uses - truth sensing, negotiations, manipulation, politics, entertainment, interrogation, search and rescue, language interpretation, psychic hotlines, 900 numbers, magician's acts, gaming, diplomacy, and more.
Other sources
There are many more powers which could function covertly or are non-obvious. I suggest looking up a superhero based RPG (book, not computer) and look through the suggestions for how to handle the various powers, as those groups have done the most thought-testing of the subject of your question.