The first priority should always be the bathroom. People will overlook some dust and clutter, but no one wants to use a bathroom that looks like they might catch something from using it. Use some spray disinfectant and paper towel or better yet, a disposable cleaning wipe like Clorox or Lysol and wipe down the sink and toilet. If need be, spray some cleanser in the bowl, swish it around and then let it sit before flushing. Dump any trash in the wastebasket.
Next should be the kitchen sink. If there is no time to rinse and stack them in the dishwasher, fill a container with soapy water and stack the dishes in there. This can be stowed under the sink. The great part about this is when you have the time to do them later, they are already presoaked.
Grab a basket or large container and stack any papers, toys or clothes that need to eventually be relocated to their proper place in the house. This can be placed in a closet or any out of the way place. Already, your home looks much better than it did just fifteen minutes ago.
Instead of sweeping and vacuuming, let your vacuum do double duty. Vacuum your carpet, kitchen and bathroom floors in one big motion. Most kitchen and bathroom linoleum and tiles are durable enough to allow for vacuuming.
You still have a few minutes to spare, so you can spend the remaining minutes in the room that you generally entertain in. If it's the living room, plump the pillows and make sure the sofa is cozy and inviting looking. We always seem to gather in my kitchen, so I make sure my counter tops are freshly wiped down and free of any really noticeable eyesores.
Finally, light a few really pleasant, aromatic candles or spray air freshener. People associate good smells with a clean environment. If your house smells clean and fresh, it will appear that way....and no one needs to know that thirty minutes ago, it was quite a different story!
Now, enjoy your company. Remember, they came to see you, not judge your housekeeping skills.