Yes, you can wait as many spins as you want, even 7-8 and then place? your bets. But it’s not worth it for two reasons: it will haeppd very rare, so you can just sit and wait whole day to make a few bucks. Lol. And the second reason no one can tell you how much reds/blacks in a row you can experience. I’ve seen 23 reds in a row one day. You say it’s impossible? Nope. It may happen very rare, but one day it will bust your entire bankroll. So, avoid Martingale, just my advice.