Hi,
New plane first flight?

Range Check then Range Check with engine running at full power.

Controls operating in the correct sense!!!! (Always a fun flight if they aren't)

Control throws as per plan/kit recommendations.

CofG

Everything has been tightened, servo screws, Prop nut, servo plugs secure, Rx aerial extended, wheel not binding (sod on takeoff),

Did I mention range check?

Post flight checks

Control serfaces secure (hinges OK), wing bolts tight, engine bolts secure, exhaust secure, general once over but in more detail than normal.

Check battery voltage (checker), a binding servo can wipe out your battery very quickly.

If you get an experianced pilot to help he will assist with all the checks you need to make.

Good luck, I hope all goes well.

And yes, breathe!