Should I tell my partner about my one-night stand?

Yes you should tell him, because he deserves someone who truly loves and respects him. Let him be with someone who does.

How do I attract a one-night stand?

Theres no time limit for setting up a one night stand. Spend as long as you want getting to know your prospective partner. Make conversation, take her out to dinner, go for drinks. Ideally, you should both be excited by everything that comes before sex, too.