When you’re getting ready for your date tonight, make sure that it gets off on the right foot. Ladies, straighten up your apartment — or, at least, that part of it that your date can see from the front door when he picks you up. And guys, look industrious.

Why? Because for men, a lack of cleanliness is the biggest romantic deal breaker. And for women, it’s laziness.

This insight comes from a report in Pesonality and Social Psychology Bulletin. Researchers crunched the numbers from separate studies conducted in the United States, Australia and Asia and came up with a list of daters’ biggest turnoffs.

For men, the top five are: appearing disheveled, being lazy, seeming too needy, living more than three hours away and having no sense of humor. The top five for women are pretty much the same, although in a slightly different order and with one major exception: lazy, disheveled, needy, no sense of humor and — hang onto your egos, guys — bad sex.

At first blush, the study might sound frivolous, but it had a much more serious purpose than coming up with dating advice. The researchers were studying a hypothesis — which they’re now convinced is true — that in choosing potential mates we tend to focus more on the negative traits we want to avoid than the positive ones we seek.

Sure, we’d like someone who is tall, dark and handsome, but we’re more interested in avoiding people who are disorganized, slothful and can’t take care of themselves.

Ultimately, are we, as a species, being too picky? The researchers don’t think so. Their report calls deal breakers “efficient cognitive mechanisms designed to cull inappropriate potential partners, allowing mating preferences to operate within a reduced target of desirable mates.”

To put that in layman’s terms, dump the lazy, clingy slob. □