How do I stop dating without hurting the other's feelings?

Honestly is always the best policy. One of the most harmful ways for the other person is Ghosting. This is when one partner stops all communication without any warning, leaving the other person confused and upset. The best way is to tell them exactly how you feel, respectfully. This might still result in them being slightly upset, but being honest about how you feel is always the best way to go for both of you.