Imagine you are the function tasked to do the conversion.
How would you do it?
One approach might be to look at each letter in the string, in order.
You might use a loop to do this.
You can use charAt() to look at each letter.
What do you need to check for each character?
You might need to know if it is a letter.
You might be interested in remembering if it is a space.
When should you capitalize a letter?
How will you record the output?
You might consider having a second empty string that you add letters to.
Do you need to add the spaces?