Rejection is rarely much fun for either party involved. It’s never nice to be on the receiving end and is awkward and unpleasant to dish out for most people.
However, it’s not really something you can avoid (nor should you). Continuing to engage with someone on a dating site with whom you have no intention of taking things further is a far more cruel thing to do than the rejection itself.
So with the above said, how should you reject someone on an online dating site?