Classic Traveller was intended as a generic science fiction role-playing game that could accommodate any specific setting or genre of play. Over the years demand for details of an 'official' campaign led to the Imperium, but similar to Greyhawk's development many regions of space seemed to be randomly generated and just shoved together, with explanations for their interactions determined later.
So let's get started.
The Game: Traveller (sometimes referred to as Classic Traveller)
The Publisher: Game Designers' Workshop
Familiarity: Never played, but have read through the books many times.
Books Required: Book 1 - Characters and Combat (there are supplemental books for expanding characters of specific services but they aren't required and I don't own copies of those anyway)
The first step of character creation is to roll basic characteristics using 2d6, applying the roles to the characteristics in the order rolled:
Social Standing 6
Since 7 is the average roll on these rolls, we can already see that this is guy is very smart and resilient, but otherwise average. He probably grew up on a poor but rugged world, or perhaps he lived a very rural life, which would explain why he hasn't received a lot of education. If I had any say in what skills he might get I would definitely give him something related to wilderness survival or hunting. For now I am going to give this man a name, Sten Laurent.
The next step is acquiring skills, this is accomplished by joining a service. Most services are of a military nature but there are rules for joining nefarious or less reputable organizations as well. Even if Sten doesn't successfully enlist into the service of his choice, he can potentially get drafted into the same service. The most difficult service to join is the Marines, but I feel like Sten would know he hasn't received a proper education and he would choose a service that might give him better training than he received on his homeworld. The best service for that would be the Navy or the Scouts, and since the Navy is harder to get into Sten goes after them. I need to roll 8 or higher on 2d6 to get in, but Sten gets a +1 to the roll due to his high Intelligence. I roll a 5 and he doesn't get in, now he must submit to the draft which is another roll. I roll a 4 which leads to Sten getting drafted into the Scouts, he considers himself lucky since that was his second choice. For my character background, I envision Sten having some foreknowledge about getting drafted into the Scouts and he doesn't have a problem with that, but he tries out for the Navy anyway because he thinks their benefits are better. When he doesn't get in perhaps somebody pulled some strings to make sure he would get into the Scouts, like an overbearing family member or a rival with connections in the Navy. This would be something I would leave open for a GM to bring up as a plot hook later.
Every term of enlistment in a service lasts for four years, and at the end of every term you get one random skill, but you must also make a survival check to see if you die in the line of duty (or get injured and are forced out of the service). At the end of every term you can get promoted (which requires a roll) and then reenlist (another roll) or you can muster out and receive a commission (more rolls). Characters who are drafted don't get commission bonuses for their first term. Without going into the minutia of the rolling mechanics I'm simply going to sum up Sten's career in the Scout Service.
Basic training in the Scouts involves learning how to fly a starship (Pilot 1) and Sten ends up taking a broad range of classes (+1 Int, Jack-of-All-Trades 1). During his second term he begins taking on more physically strenuous duties (+1 Str) and begins learning technical expertise (Mechanical 1). During his third term he's broadened his technical expertise (Electronics 1) and manages to pick up some rudimentary firearms skill (Revolver 1), he's injured however and is forced to muster out at the age of 26. During his time with the Scout Service he managed to get more schooling (+2 Education) and has saved a sizable chunk of money (20,000 Credits).
Instead of getting physically injured, I would suggest to my GM that Sten was caught in a firefight that forced him to kill several pirates but not before seeing a few close friends in the Scout Service get killed. This has left him with a bad case of panic attacks whenever he is forced into very stressful environment, which is why he was forced to leave the Scout Service.
The rules suggest using abbreviations for characters and they refer to these brief 6-digit codes as UPP (universal personality profile). A ten is expressed as an A, an eleven as a B, etc. Sten's characteristics according to this code would be 769B66. This method of expressing a character smacks of computer code, which makes me assume that Marc Millar and Loren Wiseman were programmers during their day jobs.
The way I would write the character is like this:
Sten Laurent, age 26
Strength 7, Dexterity 6, Endurance 9
Intelligence 11, Education 6, Social Standing 6
Electronics 1, Jack-of-All-Trades 1, Mechanical 1, Pilot 1, Revolver 1
Sten is a fairly average spacefarer who is smarter than his background and experiences might suggest on the surface. And now I would be free to purchase equipment, but that's boring so I'm going to skip it.