Like a traditional bike, try to maintain a cadence of 60-90 rpm with no more pressure on the pedals than if you were walking the same terrain. When you start to spin out, uoshift. When you drop below 60, shift down. This is most efficient for you, your bike's components and battery range.
Tire pressure will more dramatically impact you on an e-bike than on a traditional bike. Not only are you carrying more weight, but the extra effort of pushing against a low tire means more flats and you will use more assist (reduced battery life).
Chain maintenance is more important. NEVER degrease a chain, not even with citrus. Wipe down your chain after any wet or messy ride or after every few rides. Never use automotive lubricants on a bicycle, they are designed to hold contaminants for filters or high pressure. That means dirt becomes a grinding paste on your expensive components.
You're carrying a lot more weight in general. After you have a few hundred miles I'm be sure your check up, at the dealership, includes spoke tension.