When you start the game, your lander will be sitting in the docking bay of the mother ship. You can release your lander by pressing the firing button or wait until the mother ship forcibly ejects you. It's better to do it yourself lest the mother ship ejects you on top of an asteroid.
Fuel is a precious commodity in this game, use it sparingly. You only have 800 units of fuel to rescue 6 men. If you burn all your fuel off on the first rescue, you will have nothing to fall back on for the other 5.
When you leave the mother ship, try to navigate through the asteroids without using any fuel. Since your lander doesn't accelerate during the fall, you will be going at a constant speed down. Try to maneuver between the rocks to land on a platform. You also don't need to decelerate when landing, you just land.
Try to knock out the harder platforms first. This mean that this is land on the harder to reach ones first on the sides. A good strategy is to get the right hand-one first, then the two left-hand ones, then finish by landing on the three in the middle.
If you must use fuel, use quick bursts to get into position to land on a platform. Fuel burns up very quickly in this game so some quick shots to the thrusters should keep you out of trouble. Keep in mind, as the waves progress, the asteroids move faster and become more numerous.
Once you've landed, the little guy will run over and get in your lander. The screen will then change and you will see 3 to 6 rows of saucers blocking your path. Again, as the waves progress, the saucers and meteors get faster and more numerous. There are a couple of different strategies for this section :
1) If you only see 3 lower rows of saucers, look to the upper right or left corner. More then likely, some meteors will be coming diagonally down to the opposite corner. The best solution is to quickly blast a path through the saucers and get above the meteors trajectory.
2) If you see 6 rows of saucers, then you need to blast a path through them to get to your mother ship. Keep in mind that the fire button acts as a dual fire/thrust button. When you fire, you accelerate yourself up just a bit. In other words, no point blank shooting or you may end up taking out the saucer with your lander. When you have cleared a path, use the fire button to get yourself quickly above the saucers.
The saucers firing just drop their shots on you. Because of their numbers, you may find yourself surrounded by enemy fire. The best solution is again to blast a path through them. Once a saucer is destroyed, it doesn't come back. Also keep in mind that you can only have one shot on the screen at a time.
Once you get 1 row from the bottom of the mother ship, it will stop and open its docking bay door. If you are too far away, you will fail to dock with the mother ship and get destroyed by the top of the screen. If you hit the side of the mother ship, the man you are rescuing will unfortunately fall from your lander to his death to the planet below. Plan out the best strategy to make sure that you stay in the middle so you can catch the mother ship with minimal effort.