Starting it for the first time
Ensure your engine runs smoothly and easily when turned by hand. Ensure that all of the con rods are securely attached, in the middle of their bearing and are pulling straight from the armature of the solenoid. Ensure that the solenoids are not bottoming out when the crank it turned and that nothing is catching for a full turn.
Apply power (battery or 12V) and ensure the PCB power LED lights.
Before you engine will run I needs to know the position of the solenoids. To do this, Press BOTH buttons,keep them pressed and turn on the engine. The first solenoid should engage, ensure that the flywheel has moved around to the position dictated by the first solenoid and release the buttons. The power on the first solenoid should cease. This will have set this position (Top Dead Centre) for the first solenoid and put your engine in standby (ignition off)
To run your engine, press one of the buttons and it should start and run.
You can now use the buttons to increase and decrease the speed of the engine.
Holding both buttons together will turn off the ignition and stop the engine.
Holding the speed down button will stop the engine and reverse its direction, although you may need to give it a little push the first time you do this, as there is no auto start.
Longer term running
When you are happy that your engine runs reliably, It is a good idea to fix the positions of the bearing carriers and bearings on the shaft. This can easily be achieved by a small drop of superglue on the shaft for each carrier and against one of the 10mm bearings. Be careful not to get superglue in the bearings. It is usually easier to apply the glue via the tip of a screwdriver to prevent this.