Of course it is mate, as long as you know what you're doing and you're in profits. You could make trading your source of income if you want to, a lot of professional traders do it full time, thus making it their primary source of income, you could be the same if you know the art and what to practice it on a pro ground. But you cannot trade safely/low-risk and make profits without first of all saving a reasonable capital. I personally would never use borrowed funds for trading or investments because I think the risk is higher, I would rather use my savings with peace of mind.