"Make hay" is a common idiomatic expression that means taking advantage of an opportunity or making the best of a situation. There are several synonyms that can be used interchangeably with "make hay" to convey the same meaning, such as "seize the day," "strike while the iron is hot," "capitalize," "exploit," and "take advantage." These phrases all suggest the importance of recognizing and acting upon favorable chances or circumstances. In essence, they encourage individuals to make the most of what is available to them, especially when it comes to achieving their goals or desires in life.