Speaking for myself, the biggest shift was mindset. You can really approach business in two ways and they're completely different. Decide which is for you.
One: the artisan/boutique way. You can make plenty of money this way, it's how a lot of high-end law firms, marketing agencies, etc. run. Focus on a very high-value problem, do most of the work yourself or with a small team of partners, and be the best at it: medical malpractice cases, patio11-style marketing optimization, that kind of thing. Stay small, make a million (or more) per year, build your brand. Get work through referrals and keep charging more as you get better and more well-known. Most of your gains will come from serving clients with bigger pocketbooks, even through the work will be substantially the same (funny how that works).
Option 2: the true "business owner". Reframe from "I can make X for Y hours" to "I need to sell x million @ y% margin". Think like a drug dealer or a guy selling shoes. Sell a million dollars of product, keep 10%, you make 100k. Two million in sales @ 15% = 300k. The point is, you aren't selling yourself, you're selling a product, whether that's hours of developer labor, some kind of outcome, or even a physical product. You're a merchant. This is what it means to be a true "business owner" -- not that it matters that much, many people that go down the other path do just fine.
The main thing is to get into the mind of a (your) customer. It's no longer about the work itself, but your customer - how they find you, why they're paying you, etc. You need to figure that out.
Good luck.
(used to run an agency and now starting a software company.)
One: the artisan/boutique way. You can make plenty of money this way, it's how a lot of high-end law firms, marketing agencies, etc. run. Focus on a very high-value problem, do most of the work yourself or with a small team of partners, and be the best at it: medical malpractice cases, patio11-style marketing optimization, that kind of thing. Stay small, make a million (or more) per year, build your brand. Get work through referrals and keep charging more as you get better and more well-known. Most of your gains will come from serving clients with bigger pocketbooks, even through the work will be substantially the same (funny how that works).
Option 2: the true "business owner". Reframe from "I can make X for Y hours" to "I need to sell x million @ y% margin". Think like a drug dealer or a guy selling shoes. Sell a million dollars of product, keep 10%, you make 100k. Two million in sales @ 15% = 300k. The point is, you aren't selling yourself, you're selling a product, whether that's hours of developer labor, some kind of outcome, or even a physical product. You're a merchant. This is what it means to be a true "business owner" -- not that it matters that much, many people that go down the other path do just fine.
The main thing is to get into the mind of a (your) customer. It's no longer about the work itself, but your customer - how they find you, why they're paying you, etc. You need to figure that out.
Good luck.
(used to run an agency and now starting a software company.)