How do start up from a cold start in realistic mode?

[Freycinet]

It seems we have a lot of aces in here, so I'd love if some would just tell me how to start up the planes, from the ground, cold.

I put mixture to rich, open throttle a bit, set prop pitch to fine, switch on the magnetos, and... nothing. Can't find any starter button. Tried with the Hurri, the Bf-109...

1C ought to have added an explanation to the sim, somewhere.

Any help much appreciated!