Some people are lame like that...
Perhaps you should make him brownies or cookies and get him an im sorry card...
Tell him you are sorry (again) and that it was rude and im mature... Tell him you think he is a wonderful neighbor and it wont happen again...
That is what I would do... And then just act like nothing happend... wave high when you see him and still ask to borrow a cup of sugar every now and then...
Don't EVER go into someone's property when they're not home, unless you have their express permission. You were trespassing, and if you'd been injured in his pool, I bet that you'd file a lawsuit against him.
Just "showing him your assets" doesn't make up for anything. Are you saying that you think that you can repay people just by flashing them? Do you realize what that makes you?
Act like a grown up. Thinking that he'd never know is thinking like a child. But you've probably ruined any chances of being on good terms with this guy in the future. If I had come home to find someone in my pool, I'd have called the cops for trespassing.
He was upset because
1. He never told you you could use the pool.
2. You violated his privacy and private space.
3. His Homeowners Insurance would not cover you if you are hurt yourself on his property.
Apologize to him IN PERSON and tell him how sincerely sorry you are. Let him know you value him as a neighbor. Then promise to NEVER EVER DO IT AGAIN. When you apologize to him DO NOT be flirty or wear a bikini, The guy likes his privacy just like anyone else and you violated it.
Offer to have sex with him...
Then I suppose you wouldn't mind when you come home one day and find him in your shower? You never said he couldn't use it and giving you a shot of his ding a ling shouldn't be a problem either.
First of all you didn't ask his permission.
Second of all it's not like you guys are best friends.
And honestly, how would you feel if you found someone in your pool while you were at work all day?
And don't think just cuz you were in a hot pink bikini it can excuse you or anything, honey.
HUMANS think your behavior was very rude and unacceptable. It was also a violation of universally* known law.
You figured he wouldn't mind if you took a dip in his pool? Is that BECAUSE he never said you could? No, you're mention that "MORE IMPORTANTLY (he) would never know" makes it clear you KNEW HE WOULD object and did it anyway. Were this something we could prove it escalates your summary trespass to CRIMINAL "defiant trespass."
*meaning "even you" knew that.