Once you are passing by a nebula, you better catch the cloud as it's the only source of hydrogen to feed the engine. Running out of fuel is nearly as bad as a collision with a celestial body, your flight will end soon because you will be unable to steer.
While piloting you may want to accelerate or decelerate the vessel. Just sweep the screen up or down. It's possible but strongly not recommended to fly too slow or even backward, your score will be dropping.
Should you like to suspend the game of necessity do a long click at the saucer. When it's all back to normal you can resume the flight with the same gesture.
When you complete 15 (fifteen) training levels you will be allowed to start the real and infinite race.
Suppose you're aware that there are no sound in space. But if you don't feel like getting on with this sad but true fact you may switch on and off music and sound effects. Long click at the speaker icon enters the volume control feature.
WARNING! Long and excessive playing the game may cause dizziness, nausea, seeing stars with your eyes closed, and sleep disorder.