I'm really at a loss.All my friends have different ideas about how to do my work.
我真是迷惑了，所有朋友在我如何做好工作这件事上都有不同看法。
Well,you should have a mind of your own.
哦，那你应该有自己的主见。

I just got an offer from another company.It's killing me to choose.
我刚拿到了另一家公司的录取通知，选择好纠结啊。
You should have a mind of your own.
你得有自己的想法。

精讲部分
You need to make your own decision.
You should have a mind of your own.
Mind意为“思想，主意，心意”，have a mind of one's own意思就是“自己的主见，性格果断”。所以如果遇到朋友在某件事上因为旁人的观点而举棋不定，左右摇摆时，你就可以劝说:You should have a mind of your own.