Have everything ready before you start — this cooks fast and you won't have time to prep once the wok is on.
Use tamari instead of soy sauce throughout, GF oyster sauce, and check your rice noodles are GF (most are, but check). Cornflour and rice wine are naturally GF.
Have everything prepped and ready before you start — this moves fast once the wok is on. Don't overcrowd the wok or the beef will steam rather than sear.