I like Yoona's suggestion of basing it off of delta's. 2 years ago, I would've said 15% OTM for a week out, but with premiums as low as they are (and how little the stock moves), it's kinda like the more mature stocks where there's very little premium for not as much risk.
Like the others, I'm hunting for income by selling cc on other stocks (like COIN). NVDA was profitable until I got burned last month, so I quit while still ahead. I "might" sell a NVDA BCS to play earnings, but I'm more leaning towards buying a long put instead.
I currently have some +170p/-190p/-195c/+225c strangles open for this week and hoping that max-pain saves me. So "best OTM %percentage"? I don't think there is one, but 15% OTM (-165p/-215c) for a monthly option would probably be safe (but that's just based on gut feel with no TA to support it).