How do I tell my partner I have an STD?

Dear Edahn,

How/when should one tell their special someone that they have an STD? I just had a guy tell me last night right before we started to have sex and it kind of ruined it for me. Made me think if he could have disclosed it sooner, would I still be with him, or in actuality not return any of his calls.

Clever guy. He anticipated that you'd refuse his advances and chose a time where it'd be easiest for you to accept the risk and do it anyway. I don't know what his delivery was like, but if I had to make such a disclosure, I'd probably try one of these two approaches:

1. The Casual Approach

While pretending to do a crossword puzzle on the date just prior to having sex (i.e., the second date) I'd say something like this:

Me: "I need a disease, 9 letters, rhymes with 'pizzeria.'" 
Her: "Gonorrhea?" 
Me: "Yeah! Thanks! Hey, that totally reminds me. I have syphilis. Okay, now I need a 6 letter word for 'sly' beginning with a 'c' and ending with a 'y.' It's not 'choppy'..."
Her: "Crafty?"
Me: "Yes!"
Us: [Coitus]

I'll bet most of you who just read that are thinking "he didn't even tell her about his STD!" Look again, guys.

2. The Direct Approach

I'd arm myself will all available statistics and information about the STD so I knew how to field any question as well as avoid giving it to my partner. I'd be ready to explain to her exactly what we'd have to do to avoid transmission (protected sex, when we couldn't have sex at all, and how long that would last) and make sure to highlight the good parts, maybe with a little humor; for instance, I might say: "we could still have sex the other 330 days of the year. Some days we could even have sex twice to make up for the deficit, which I would be amenable to."

The biggest stereotype about STDs like herpes, chlamydia, and gonorrhea is that you contracted them by sleeping with a lot of shady people. I'd address that concern by explaining how I actually got it while stressing the sympathetic parts ("she said she was totally clean," or "I didn't think donkeys could carry that") and minimizing the parts that made me seem like a hooker. Note: For those who actually got the STD by sleeping with a lot of shady people, you can instead explain how you've changed and now only sleep with one shady person. If you're still sleeping with a lot of shady people, then, well, the chances are the girl you're about to have sex with is dirtier than you are, in which case you don't have that much to worry about, save of course contracting an additional STD to complete your collection.

I'd probably make the disclosure a date or two before I felt like we were going to get down and dirty. I'd start the conversation by genuinely asking her if she's been tested recently (nothing too funny) and letting her answer first; then, based on her answer, I'd explain my situation using the above considerations. I'd put it all out there and tell her that I'd understand if she didn't want to get sexual yet; at the same time, I'd ask her to see that I'm not a total whorebag just someone like her who made a mistake, that I'm no longer careless, that transmitting it was unlikely after taking simple precautions, and how badly I wanted to be intimate with her. If I kept getting turned down, I'd start picking up partners at more sympathetic venues.