Unemployment is a majorly complained-about problem. Workers dislike the inherent poverty, and companies dislike having to search for, hire, and continue to motivate workers. So let's make it easier to get a job, which should benefit everybody. More people might quit, but they'll quit in favor of a job they prefer.
Various human traits are involved with successful employment. There are a number of models I could draw from, but I'm going to draw from Dungeon's and Dragons, which put together a simplistic model to enable people to pretend to be people very different from themselves. (If forced to play their own self, D&D groups would be radically unbalanced.) It produces six scales of traits, three physical, and three mental, which are randomly generated at the start of play. (You roll three dice to get the numbers. Everyone WANTS high numbers, but the dice effectively take it out of human control.) Over simplistic, perhaps, but if I make this system too complex, it'll collapse under its own weight.
Personality also makes a difference. A salesman and a computer programmer will need wildly different personalities to succeed in their respective fields. If you forced one to take the other's job, they would be miserable. Again, I have an oversimplified model of the Myers-Brigg's tests that boil personality down to four key traits. Introversion vs. Extroversion, Intuition vs. Sensing, Thoughts vs. Feelings, and Perception vs. Judgment.
I'll talk about D&D for a while, if you're familiar with the game, feel free to skip the next few paragraphs or so. I'll also talk about good ways to improve yourself in that field, so it may be good reading anyway.
The D&D traits are strength, dexterity, constitution, intelligence, wisdom, and charisma. The three-dice system generates numbers between 3 and 18, so 3 was arbitrarily decided to be the lowest-end of this trait found in humankind, and 18 the highest. A person with 3 strength breaks their arm while toweling off after a bath, while a person with 18 strength weight-lifts for fun and can easily ram through doors and rip handcuffs off their wrists.
Strength is, of course, having big muscles and a great ability to exert physical force. The best way to improve yourself, if you think you're deficient here, is to lift weights. Also, avoid watching television, as sitting still makes your body reabsorb the muscle.
Dexterity in D&D involves both the ability to move out of the way of obstacles, reflexes and so on, and also the ability to do fine work with your fingers. I'd split this for my model into body-dexterity (do gymnastics, dance), and finger dexterity (put this tiny gem into this ring and close the tiny wire around it). This is again improved by practice, so dancing and gymnastics will, if done daily, improve your body dexterity, and doing small-scale work like knitting or making miniatures is a great idea for finger dexterity.
Constitution is a general healthiness. A person with great constitution can both fight off disease and keep exerting themselves for hours. Constitution isn't technically a requirement for any job, but companies would prefer to hire workers with great constitution, as they will have fewer sick days, and put less strain on the health insurance. To improve yours, get regular aerobic exercise, eat a varied diet, but not too much or too little, and be sure to sleep consistently, enough, and at the same time every night. (Human bodies are odd about sleep!)
Intelligence is a general catchall of the ability to reason, learn, and remember. It is controversial, because it is ill defined and a major part of human identity. (D&D asserts that all animals have an INT score of 1 or 2, much much lower than any human. This seems...dubious.) Reading is great for this trait, if you think about what you've read. Education is also great exercise for it. This actually matters less than most people think it does.
Wisdom is an ill-defined trait that enables you to notice things. A person with high wisdom is observant, contemplative, and understanding. A person with poor wisdom is absent-minded, distracted, and impulsive. A high wisdom score is essential for any knowledge work, or unpredictable field. Improve yours with quiet reflection, meditative hobbies, and perhaps a trip to a museum. Avoid jangly, distracting mediums such as television.
Charisma is the ability to influence people using charm and force of personality. As a word, it derives from the Greek for "favor,' as they assumed that charismatic people were blessed by the gods. Anyone who wishes to have a public-facing job will need this. There are a lot of disagreements as to if you can influence your own or not. The closest one I can think of to a reliable improvement in charisma is acting classes. It also helps to be sociable, hygienic, and witty.
Okay, the D&D nerd-out is over. You may resume reading.
Now the Myers-Briggs. These two psychologists felt that all people had all eight of these traits, but balanced differently, with one more profoundly showing through, and one only meekly and privately. The one that is shown vs. the one that isn't reveals traits in personality. Let's go over the four dichotomies.
The first is introversion vs. extroversion. An introvert is more concerned with his or her own internal self and ideas, is worn out by social contact (whether they seek it or not), and tends to have a few close friends. An extrovert, in contrast, is more interested in other people, feels built up and excited by other people, and feels "faded away" when alone. They have many friends, most of them more casually than the introvert.
The second is Intuition vs. Sensing. The Intuitive types seek abstraction and big systematic understanding, and the Sensing types prefer the concrete, direct, and small details.
The third is Thinking vs. Feeling. Thinkers put weight into logic, Feelers demand emotional positions. A Feeler will find a Thinker cold and inhuman, a Thinker will find a Feeler irrational and silly. (But both have important roles to play in a civilization.)
The last is Perception vs. Judgment. Perceivers want to keep the options open until they have enough evidence to make a decision, whereas Judgers want to have a plan ahead of time.
Myers and Briggs both assert that only the person themselves has true knowledge about where they would fall, but a number of tests on the internet can offer their advice.
Next up, how to use these traits to find a job you'll be happy with.