Don’t do it yourself. Use one of the online generators if your business if fairly vanilla wrt to terms and privacy, or get a lawyer from https://upcounsel.com to customize their template for your use case. I went the lawyer route 4 years ago because the generators weren’t as well established then; it wasn’t as expensive as I was afraid it would be (~$500 IIRC) and it got the job done, but the doc quality wasn’t stellar either.
Where a lawyer really helps in the long term is if they get familiar with your business and can warn you about risks that you don’t even realize you don’t know about. It’s your call if/when to establish such a relationship, though – I didn’t until a couple years into running my business, and with a different lawyer than the one who wrote the terms and policy docs.