I think Blast's suggestion is an excellent one.

Your history isn't baggage, it's life experience. It means you can walk into a situation and pick up the key points very quickly.

I've been making my living at this sort of thing for nearly two decades. A few key lessons I've learned:

1. Your network is everything.
2. Your network is everything. There are six degrees of separation between people who trust your work and every potential client on Earth.
3. Feed your network beer and hot wings, on a regular basis, and it will feed you.
4. Deliver what you promise, unless you are dead.
5. Under-promise and over-deliver.
6. Agree on a recognized standard at the start of a project (Chicago Manual of Style is good for tech writing). You'd be surprised at the extensive peeing matches regarding the serial (Oxford) comma.
7. Make the client look good.
8. A job is always worth more to the client before it's done as opposed to after.
9. Put agreements in writing. If it's not in writing, it doesn't exist. Good paper makes good friends.
10. Be pleasant in negotiations, but always be prepared to walk.
11. If things are going sideways on a project (personalities, other fatal B.S.), withdraw as gracefully as you can without screwing others. Use the excuse "given these factors, I don't think I can add value, so I think it's best for the project that I withdraw." Always take the high road. Bad news about problematic contractors travels faster than light.
12. If you're subcontracting (happens a lot), always dance with the one who brung ya.

Good luck!
Doug