Use a sniper rifle rather than a shot gun.  Focus on a clear business plan, go for quality vs quantity. 

I would have IMMEDIATELY been more careful in client selection. Like 2 minute date. First red flag out, nope, nope nope! 

I did not understand the value of leveraging my SOI for success when I started out. Big mistake! I wish I could do that part of my career over again. Hindsight is good but I can't undo the past.

Develop a working by referral system. As John Juarez said... when agents are new they don't always understand the value of leveraging their SOI and data base.

I would have transitioned to an independent broker sooner than I did. 

I would get a mentor on day 1

Nothing.

Learn the paperwork, rules and regs, people language (body included) and then to pick a spot and work-it until I am the go-to for the area

Good Question. Curtail all extracurricular activities until very well established

Stay in touch with clients from day one.

Mentor, business plan and one niche at a time. Networking all the time with follow-up.

I dont know if I would changed anything, every lesson was an important one.

I got in when rates were 16.5% adjustable so every step was calculated and considered to sink or swim. I think agents starting out when the real estate treadmill is flat and easy suffer later when the incline steepens William Piotrowski . 

I would not change anything I did

If I were a new agent today, I might consider starting on a team. Whether I do that or not, I'd be more business minded. That is something many brokers don't talk about or teach. How to set up and run a business. I've learned from trial and error over the years. And still learning.

And as Joan mentioned, have a better system for staying in touch with past clients and sphere.

I would meet people face to face more than when I started.  The phone is great but in person is far more impactful

I would not have started with a team but with a one-on-one mentor instead. Also, don't let company "culture" prevent you from getting education from other sources (i.e. local/state association).