The ongoing Lincoln Project story reminds me that I haven't met anyone in politics yet who really understands how journalism works and how to handle a bad story. The Winning FormulaTM is also the right thing to do, but it involves a lot of humility and relinquishing some control.
First, don't lie to reporters. Ever. Even if you fool one, another one will find you out. And there are a lot of people who naively think they will fool ALL the reporters. This is just arrogance.
Don't try to intimidate people you suspect might be sources. It gives them more of an incentive to be a source, and it usually has the opposite of your intended effect: it encourages other people to talk to reporters.
If you know something is going to break, tell the story yourself, truthfully. There's a line from some Chris Matthews book that is actually applicable (and he did not do): hang a lantern on your problems.
Don't get defensive. It makes you sound like you don't *really* think you did anything wrong.