This happened to me about six months ago -- I had a small team, but we landed several clients at once and I didn't have the right systems in place. Nothing blew up, but I was stressed while I tried to do a lot of the work myself and get the right people and processes in place.

If you're pretty confident you can get the clients, I'd start training someone NOW to do the things you're doing, so you can hand that work over and focus on onboarding new clients or doing new work. If you're bringing someone on in a consultant/part-time role, it's less important to rope in the revenue/client first because that new team member won't cost you so much that it puts your biz at risk.