To start faster and more confidently:
1. Stand straddling the frame.
2. Position the forward pedal for your first pedal stroke with the crank arm at about 45 degrees up from horizontal (45 degrees down from vertical).
3. Place your foot on that pedal.
When you want to go:
4. Stand up on the pedal and remove your other foot from the ground. Your weight will accelerate you forward.
5. Place the other foot on the other pedal and be ready for your next pedal stroke.
You can sit down after steps 4 or 5, or later, depending on how much power you want to exert to accelerate.