In addition to the above --all great advice-- I'd like to add that you need to get them to like you.

That is the differentiator. You need to stand out, but in a positive way. You can't just be a "purple cow".

A customer first needs to know you exist.
Next you need to build trust.
Then they have to have confidence you can do the job.
And finally you have to be the one they want to hire.

Know -> Trust -> Confidence -> Like

All other things being equal, they will choose the one they like best, the one who they want to succeed.

If they're hiring an unknown, they will either choose based on price or preference.

To be liked, you need to have a personal connection. So put out a personality. And that doesn't mean try to please everyone. Because you can't. And by trying to not offend anyone, you will fail to express your personality.