Most people would say it is not safe to ban all day. Human type activities keep you the safest. Taking a break and doing other kills and quests is best.
The breaks are really up to you. The more the safer. I usually don't like to bot over 6 hours at a time but have went 20 without a ban so it is up to you.
You will get banned, you will learn your own style, no one can tell you how to bot safely 100%.