How do you get a patent description proofread? Is it a service offered by patent office for free as long as you paid the application fees, or is it something you need to get proofread by someone? Also, is there a standard way to describe a patent, or any style is fine as long as the patent description can be understood?
Patent agent (not attorney) here. I do not practice.
I don't recall it being offered by the patent office, although if you browse the uspto.gov site, you may find some programs to help first-time applicants who don't have attorneys.
It sounds like you haven't started yet. There is something called a Provisional application, which does not give you any patent rights but preserves your priority date. It does not have any claims, which means you don't need an attorney. You have one year after that to file the "real" patent. Start there.
Now the bad news: a "real" patent has claims, which are highly technical and you cannot do them yourself. You will need to pay an attorney or agent to do it for you (again, there may be aid organizations to help out).
Even more bad news: the Patent Office almost always rejects your patent at first, and you have to answer them and/or amend the claims. More $$$.