go for it

to do anything you have to in order to get something

尽力争取;不遗余力去做

A: Do you think I should sign up for the course? It's quite expensive.

你认为我应该报名参加这个课程吗?还挺贵的。

B: If you're sure you'd like it, then go for it. You'll enjoy it.

如果你确定自己喜欢，那就去做吧。你会非常享受的。