Expecting second household income. How to handle?

I’ve been in the Air Force for two years and my wife has been a stay at home mom for the duration of that. My wife is starting a job in a couple months that will pay ~70-80k annually. How should we handle this extra income? We have lived fairly simply off of my E-3 income, but something has always came up that has prevented us from saving up a significant amount. I’m leaning towards opening up a HYSA and depositing my wife’s paychecks into there until we have ~12 months expenses saved up. If we can get to that point, we planned on putting everything else into a S&P 500 ETF after that. Is there anything else we should be doing or considering?