My gaming group and I had a go with the example scenario last weekend. Having played Year Zero and Genlab Alpha and being in love with the card decks as reference tools, I copied out the text sides of the Chassis Cards onto blank playing cards but that was all the preparation I made as GM besides reading the PDF through.
I was very loose with the story background; their briefing was basically, "You are robots in service to <probably-not-a-spoiler-but-just-in-case>, the humans left decades ago but you've carried on working until now, when you find yourself wondering where they've gone and why the world around you suddenly looks in such poor repair. You've just been reassigned to an EEU and given your first work order. How long ago you became self-aware is up to you - more than a month though and I expect you to have a couple of dice in Question."
We'd normally put more effort and time in than this but we were on a deadline; my friends run the Critical Twits podcast and should be giving their opinions in a review episode released this coming Tuesday.
Once character gen was finished, I gave a very brief description of what they could see on their monorail ride into District 6, the almost deserted highway they journeyed down next and then launched into the material directly in the work order. Their questions to other robots and a few Datamine rolls took them straight to the main action and I used four of the suggested events.
My advice for a proper start to this game is to have all your players first read Chapters 1, 2 and 7 as a minimum. Creating their own characters won't take long, even if they're completely new to the Mutant games, so long as you can explain what the Programs do in the game. Have Chassis and Module cards ready if you can, whether you scribble them out by hand like I did or print them out at index/playing card size, because it'll be so much easier to make sure that nobody duplicates anyone else. In hindsight, I'd have copied the card fronts to my preferred publishing program 8 to an A4 page, inverted the colours to save on ink and just printed. Oh and watch out for the last Chassis card, as the text is still in Swedish. The art makes it plain but unless you're printing that out too, we found the internet can translate it clearly if you want.
As Tomas has said, thanks to the transport system and the Collective all being online wirelessly, the PCs don't need to meet up until they're in District 6 and possibly not before they arrive in the opening scene of the adventure. You can give each player a description of the local area around their charging station if you want to but it's not really important to start with and in my opinion, it's more fun to get players to create that sort of detail themselves as a way of getting invested in the world.
@Orlagh08, when you say it's your first time playing, do you mean playing a Mutant game or roleplaying games in general? Mechatron does seem to me slightly more complicated as a starting point than Mutant: Year Zero but still far easier than many other RPGs out there. Learning as you go is definitely the easiest method, and don't worry if you forget about modifiers to rolls or other details so long as you are having fun. I've played the Mutant games for two and a half years and still forgot to use the Datamine modifiers that are in Chapter 7.
Having physical cards does make the game easier but so long as everyone involved has time to look at the Chassis and Module options, then all you really need to print out are copies of the character sheet. From what we've seen so far, this might be the best Mutant game to try and play alone but I think you'd enjoy it more with extra people. The campaign named Ghost in the Machine will have secrets that can be discovered by the characters and you'll lose that surprise element if you're playing alone. Even ignoring the campaign, if the Work Orders are anything like the Threat system in Mutant: Year Zero, then most will have a title, tell you what happens as a result of completing or failing the mission and feature a short sentence or two that a GameMaster is expected to turn into a story. If that's something you're likely to enjoy then go for it! You'll want to have more than one character to use, even if you're the only person playing.
I had 3 players plus myself when we tried Mechatron but we have often played Year Zero and Genlab Alpha with up to 6 players and a Game Master.