SF = friendly people
ST = serious in business, reliable, hard working
Here are some very brief descriptions I came up with:
NF: These people are highly empathetic and idealistic. They have an incredibly advanced intuitive understanding of people. They are highly spiritual and morally enlightened. Their goal is to understand themselves and others. At best, they are creative and prophetic individuals who want to make the world a better place. At worst, they feel tortured and behave in an overly-theatrical manner. Perhaps prone to depressive episodes, bipolar disorder, and dramatic neuroses. Life for male NFs in particular is difficult, as it goes against their prototypical role in society.
As children, they tend to be gentle dreamers. Almost adult-like in their understanding of human emotions. Very kind towards peers and animals. They usually love nature. In highschool, they may be seen as "bohemians" or "emos" who strive to stand out from the crowd. On the contrary, they may also be seen as modest, unassuming, eco-friendly stoicists.
How to recognize: They generally tend to have a very individualistic, theatrical, or minimalistic appearance. They are prone to speaking in hyperboles, making small things like a paper-cut look like Armageddon or symbolic for the misery of the world.
Career and interests: Tend to gravitate towards fields were they may help people or express their creativity. Suggestions: psychologist, cult leader, writer, preacher, painter. Hobbies often include psychology, philosophy, charity work, yoga, and anything related to nature.
Distinctions: NFJ = Strive to help people as well as understand their emotions and their roles in events. More mystical, spiritual, and openly caring.
NFP = Strive to understand their place in the world, as well as to express "their true self." More individualistic, "counter-culture," and artistically expressive.
ST: These people are very pragmatic and matter-of-fact. They are the type of people to say "just the facts, ma'am." They have a penchant for hands-on work, factual information, and "getting things done." They are quite good at either mechanics or organization. Their goal is to deal with things as efficiently and pragmatically as possible. At best, they are skilled realists and at worst they are narrow-minded. Prone to aggression and psycopathy.
As children they are usually very hard-working. In school, they are usually athletic "jocks," hall-monitors, quiet mechanics, or members of the "popular" crowd.
How to recognize: simple, down-to-earth appearance. Speak in a rather dry manner. Occasionally somewhat aggressive in their speech, whether jokingly or not. Most prone to criticize. Also prone to use expletives frequently.
Career and interests: Manager, stock-broker, accountant, professional athlete, engineer, mechanic, pilot, soldier, fire-fighter, police officer, investment banker. Hobbies are usually predominantly sports-related. The introverts for recreation tend to focus on things that require great skill and concentration, often involving building things.
Distinctions: STJ = strive for "success," wealth, and building a family. More organized, traditional, and driven by duty.
STP = strive for independence and mastery of skill. More impulsive, mechanically and/or athletically talented, and less driven by societies norms.
SF: They are very caring, sociable, and at the same time, realistic. Very skilled at socializing, communication, and otherwise dealing with people. There goal is to care for people and to build relationships. At best, they are kind, joyous, and helpful. At worst, they are overly-anxious and hedonistic. Prone to borderline and dependent neuroses.
As children, they are very outgoing and understanding. In school they are the typical in-crowd, especially for females. SFJs tend to behave more like role models and are often the "teacher's pet." SFPs tend to be a bit more artistic and unruly.
How to recognize: Very focused on their appearance. SFJs want to look more traditional while SFPs prefer a "wilder" or festive appearance. Collectively, they generally tend to speak in a warm manner, often riddled with emotional expression of various sorts.
Careers and Interests: psychology, art, music, acting, (more suggestions?). In their free time they tend to socialize, party, watch films, eat and drink, etc.
Distinctions: SFJ = as previously stated, more traditional and low-key. Their goal is to nurture. The prototypical mother.
SFP = more wild and outgoing. Their goal is to appreciate life and indulge their senses (perhaps the most sexual of all types).
NT: These people are very academic in their interests. Combine the technical skill of the ST with the creative nature of the NF and there you have it. An NT. They are very imaginative and driven. They tend to philosophize everything. Very speculative. Their primary goal in life is to gain an understanding (and perhaps control) of nature through research and the collection of knowledge. At best, are innovative, thoughtful, and daring. At worst, they are cold, unkind, cynical. Prone to obsessive-compulsive behavior, mildly autistic behavior, and schizoid/schizotypal neuroses. Often become extremely detached from reality, which may serve either as a benefit or problem, depending on the situation.
As children, they are often either quite solitary, absorbed in taking things apart, or quite out-going, always asking questions (perhaps to the irritation of their elders). In highschool, they are often the "nerd" or "geek" and will typically be labeled socially backwards by many. Occasionally, they will develop a rebellious edge, often resulting in them being regarded as mavericks, pranksters, or trouble-makers (this especially applies to ENTXs).
How to recognize: Dress simply and efficiently, though often with a touch of quirkiness. Frequently appear unkempt and unconcerned of their appearance. They will generally speak in a precise and occasionally terse manner, often utilizing a sophisticated vocabulary (often to the extent of appearing pretentious).
Careers and interests: Have a love for theorizing and systematizing. Computer specialist, military commander, scientist, analyst, lawyer, inventor, stand-up comedian, philosopher, sci-fi writer, mathematician. Their hobbies are usually quite similar.
Distinctions: NTJ = more driven, ambitious, and pragmatic. Often have quite an ability to strategize everything.
NTP = lazier, less driven, and more idiosyncratic. Are more attracted to inventing or configuring than strategy.