text.replace(/(^\w|\s\w)/g, m => m.toUpperCase());
// Explanation:
// 
// ^\w : first character of the string
// | : or
// \s\w : first character after whitespace
// (^\w|\s\w) Capture the pattern.
// g Flag: Match all occurrences.

// Example usage:

// Create a reusable function:
const toTitleCase = str => str.replace(/(^\w|\s\w)/g, m => m.toUpperCase());

// Call the function:
const myStringInTitleCase = toTitleCase(myString);