what to do between now and September when rate increased ? For both short and long term investor

I saw that overall price went up in the morning of Friday, crashed only after the Powell speech. The rate hike is now unavoidable with 50-75 basis points on September. I still have 50k cashes available, should I just stay out of the way ? or should I invest some money now given many big-company stock probably under-valued.

If you're a long-term investor, what would you do now ? how about if you're a short-term investor