Making compare() function more elegant

I have this code:

function compare (a, b) {
  let comparison = 0;
  if (a.essentialsPercentage < b.essentialsPercentage) {
    comparison = 1;
  } else if (a.essentialsPercentage > b.essentialsPercentage) {
    comparison = -1;
  } else {
    if (a.skillsNicePercentage < b.skillsNicePercentage) {
      comparison = 1;
    } else if (a.skillsNicePercentage > b.skillsNicePercentage) {
      comparison = -1;
    } else {
      if (a.startDate > b.startDate) {
        comparison = 1
      } else if (a.startDate < b.startDate) {
        comparison = -1
      }
    }
  }
  return comparison;
}

What would be the most elegant way of writing it? It doesn't seems nice at the moment.