Morning Helen - I wish I had more time today to send you a longer reply. Happy to chat if you need further advice. I just went through this with Chango, we had to take it from $0 to a run of $100m in 5 years, and as CRO I went through all the pains of that.
You have received some excellent advice above, particularly around process. However, I have a slightly different view. It is important for you to be aware of what the right process is, but not essential for your first seller(s) to be expert at it. Typically at the start you need someone scrappy, someone who can operate on their own, they have contacts, they can knock down doors and they can push for the deal. You might find these people are not particularly great at sales team process at all. They are tyoically hungrier for the deal, they will take a deal more weighted to commission than base salary, and they can be your early lifeblood. Be aware that as the organisation grows, they will need to be replaced, or they will need to accept someone more senior coming in above them to run the growing team. Therefore be careful with inflated titles at the start, and set the right expectations. The wrong setup could mean you get someone up to the right speed and pipeline, and then you lose them as new blood comes in, and you take a step back.
Think about how quickly this team will grow. If it's to many sellers in a short time, focus more on process. If it's a slower growth than that, focus on instant revenue, and someone that represents you and your brand.
And don't beat yourself up over sales commissions - they has never been a perfect sales commission structure, they are all flawed in one way or another. Get familiar with various models, understand commission splits, spiffs and bonuses. Know the benefits of 4 quarter payouts over 5 and vice versa. And then pay them well. Allow for product failures that aren't their fault. But don't let that go to far, otherwise a good salesperson will try and walk all over you in the future.