As much as you possibly can.
No, give everything away.
Most information you are giving to people is in the public domain and therefore isn’t really yours. So what separates you? The ability to be generous and be a resource of your industry. A few weeks ago, I was at MarketEDlive and one of the speakers Chris Marr said that people and businesses should aim to be the: “Wikipedia of their industry”.
In being a resource in your industry, this means that you will be referred to, considered as trustworthy and be the “go to person” (Thought leader) in your industry. Through being the reference point of your industry, it means you will end up getting more sales.
Still worried about giving information away? Ask yourself, what do people exactly pay you for? If you are a lawyer or an accountant, people pay you for the process, implementation and execution of your knowledge NOT JUST THE INFORMATION.
Let us say you gave all your information away today, I guarantee that your customers or competitors would not be able to just replicate your business. If they can, then you need to question the value that you give.
It is easier now than ever to be the “go to person” in your space…
But you have to be consistent and keep on improving…
So be generous, be the “go-to person” and give information away.