So, here's a free lesson to any guy trying to date multiple women. You have to treat your place like a crime scene...leave no evidence. Not regular cleaning either.  I'm talking about lint rolling your bed to get any accidental hair left from another girl, including the pillows.  Rub some of your dirty laundry on your pillows, so the other girl will suggest that you wash your sheets.  Don't have another girl come over when your sheets have just been washed, it's suspicious and she will immediately launch an internal investigation.  

Place any and all items not belonging to you that were left overnight (earrings, bracelets, fish net gloves, etc..) in a designated lost and found box to be hidden at all times, preferably a shoe box.  Get a mop or swifter and go over all of the bathroom floors to pick up any hair that may have fallen on the ground due to women "shedding."

Empty every trash can in your house, especially the ones in the bathrooms.  This is one of the first places girls look.  I'm sure no girl I talked to ever noticed, but there was never any garbage in my trash cans. Who doesn't have trash in their garbage cans? This guy, that's who. Which isn't a coincidence; no one...and I mean no one is that clean.

Finally, when the new girl comes over you have to be banging something into the wall with a hammer.  Preferably a shelf.  As soon as she walks yell, "goddammit, I can't get this shit straight."  She will offer to help you and ignore the sweat dripping from your forehead that was from the pre-marital sex you just had with another woman.