Graduate programs look at grades, especially in math courses and econ courses, and usually look at GRE scores (although some programs have dropped the GRE requirement). The requirements for math and a good score on the quantitative part of the GRE are much tougher for PhD programs than for master’s programs.
You will need three letters of recommendation. For PhD programs, the letters should almost always come from people involved in academic research. The letters are very important, so you will want to get to know faculty early. You also need letters for master’s programs, but they are much less important.
For PhD programs, evidence of having participated in economic research is generally very important. This is another good reason to find ways to connect with faculty research projects.
Life experience, work history, being well-rounded don’t’ matter very much. You should do a good job in writing personal statements or research proposals (when requested), but these are less important than in many other disciplines. Unlike many other academic areas, in economics one applies to the department rather than to work with a particular faculty member. Do not contact individual faculty about attending the program before you are admitted.
For extended advice on the path to PhD programs, take a look at https://startz.weebly.com/getting-an-econ-phd.html. While written for UCSB students, most of the advice applies everywhere. More such sets of advice can be found at https://www.aeaweb.org/resources/students/grad-prep.