Ok,
my question is, how much coins you keep in wallet and how much on exchanges?
Is it like 50/50 or more like 90/10?
I have the same question, I have everything on my Bittrex wallet and I keep on reading people who recommend having an offline wallet... I don't know if it's that convenient. Is it unsafe to have it in the exchange?
It is not safe. When you keep your bitcoins in an exchange, It is like that you have trusted to a person to keep your bitcoins and he can steal them easily. keeping coins in this way is convenient, but it's risky