1. First things first, get the gardener to put the cover on your pool when your not using it. During these hot days, you can prevent evaporation and save on heating. Its down to Labour education failings that pool management isn't taught in schools
2. Don't empty your Jacuzzi after use, let your servants have a go. Normally, of course, you'd instruct your man to drain and clean your Jacuzzi once you've finished but why not charge him a few quid for the honour to be allowed to use your water.
3. Use a hosepipe ban loophole. This is a clever plan, hosepipes are banned but a chain of lads with buckets is completely above board; get a few of the staff onto it.
4. Replace all your lawns and plants with plastic equivalents. Think about it; these don't need watering, cutting or pruning - so there's a saving on staff.
5. Spend the summer in your Swiss chalet. This is an obvious move, but needs some planning - you need to get the UK staff onto zero hours contracts so you don't waste money paying them when your not there. If you need extra staff out there, why not get them jobs as Ryanair cabin staff - then they can fly out for free.