Welcome again. Being reletively new myself I've found that there is plenty to learn but that mostly it's basic common sense, a little patience, a bit of preparedness and some foresight.
When I first joined the forum one of my first questions was 'What are the most frequent problems people encounter?'
Some of the most relevant and helpful responses were:
Flat tires- get a bottle of the green slime at an auto parts store (cheaper than at the bike stores)
Failure of the CDI- Have a spare handy, the best price around and quick shipping is bicycle engine kit, bike engine, bicycle engine, bicycle motor
located right here in Colorado
Failure of the magneto- They are cheap and also available at the web address above
Fouled spark plugs- carry a spare most recommend the NGK equivalent rather than an exact replacement
Chain failure- BMX chains from bike stores work well and if your kit came with a 410 chain instead of a 415 i would change that out before anything AND when it comes to the master link make sure that you put it on facing the right way!!!! My personal recommendation would be the BMX chain, its plenty heavy duty and you can get replacement master links at the local bike shop though I think they might be available for even less for bicycle engine kit, bike engine, bicycle engine, bicycle motor
Build it tight, the tolerances aren't the best in the world with these Chinese motors but a little well applied gasket sealant and locktite rather than just tossing it together with what is supplied can make a world of difference, where the white sheathing that protects the wires comes out of the magneto housing silicone around that and where the wires exit the white sheathing itself, keeping water out of the magneto can save lots of headaches.
Beyond that do a pre-flight check daily or at least very very regularly the vibration does tend to loosen things up and this is where the locktite on the threads and double nutting bolts wherever and whenever practical.
Most importantly have a safe ride, never assume anyone sees you and always figure that the nearest car(s) are always out to get you.