The first thing to do is to activate the Mk.I Solagen which is already in stock in the energy module. Once this is up and running, it's simply a question of initiating the Resource Complex to get enough material to build a Mk.II. Once the Mk.II has been researched, you'll find that there isn't enough energy to build the thing. Turn off the Resource Complex, build the Mk.II and then turn it back on again. After that, it's simply a matter of researching and building increasingly powerful Solagens up to the Mk.X. Don't worry about the failed Mk.III. Simply use the Mk.II which should be in store and repeat the process.
Once the base is operating properly, you have a number of options. But before many of the items can be built, extra minerals are needed. To get these quickly, and simply, research and build a small fleet of Grazers. These can continually ferry small amounts of much-needed ores from the asteroid field.
The central part of the game focuses on the growth and expansion of the moon and it's colonies. This is a matter of finding which moons or planets provide the best sources of raw materials, setting up colonies and shuttling to and from these. The colonies provide minerals and ores, while the moonbase sends replacement Solagens, Fighters and Orbital Lasers.
The latter equipment - as if you hadn't already discovered - is employed in the continual fending off of Martian attacks. Orbital Lasers are very effective, but can only be used once: obviously it's best to keep a reasonable store in each colony and the Moonbase (later on in the game you'll need a full complement of lasers on the moon so keep building !)
To find more info about the Solar system, continually build and launch probes. However, don't bother sending them to the inner planets, Mars and it's moons, Jupiter and it's moons, or the asteroid belt, since they either get destroyed or yield no/useless info.
The key to completing the game is Triton: probe, research and colonise as soon as possible, for reasons which will become clear later.
When reports of Martian flu come in, research and produce the required vaccine. Don't just ferry it to the infected base though, but produce enough for all colonies and the Moonbase since the strain is virulent and soon spreads throughout the inhabited worlds.
At some point you will be informed of the crashed Martian Fleet Carrier, and the details beamed back to the Moonbase. Research this immediately: it's important that one be built. However, you'll find it takes rather a lot of materials !!!
Once the fleet carrier is built, fill it full of fighters and head for Mars. While in orbit the carrier is attacked by a fleet of Martians, at which point all the fighters should be launched (lower right icon on left hand side). A ferocious, if slightly tedious battle ensues but the Martians should eventually surrender.
After this, Mars can be colonised in the usual way. The colonists then find plans of a Martian transforming machine, capable of making the Earth's air breathable. Again, this should be researched and built ASAP. However, you'll find that the stock of chromium is pretty much nil. This is where Triton comes in: you should, by now, have enough chromium collected for shuttling back to the moon.
Once the Terraformer is built, you'll find that even the Fleet Carrier isn't large enough to carry it to Earth. Don't despair: the researchers redesign the ship so that the Terraformer just fits in. The newly customised juggernaut can now take it to the Earth, although it cannot take off again.
While the Earth is being transformed, previous reports of a huge Martian fleet prove to be true, when the Moonbase is attacked by over 200 fighters! At this point the stockpile of Orbital Lasers - up to 16 - should be used, prior to launching your fighters. Even after all this, it stands a very good chance that the attack cannot be repelled completely, and the Moonbase still gets duffed up a treat. In this case you'll find that the Moonbase's population has been reduced to zero. Don't panic: send a couple of Carracks to the moon to dismantle them. The population increases by 80 for every Carrack destroyed.
Having survived the Martian final assault, it should now be just a question of time before Earth is colonisable. In the mean time, all your colonies start declaring independence. As long as you have a good stock of materials, don't worry about it. When a report comes in stating that Earth is once more habitable, build the necessary SIOS, and send it to Earth, and then throw your joystick around the room, and out through the window, as you are greeted with the naff end sequence !!