Drive to the walk - get muddy and wet - drive back - wash the dog off.
Some of you likely do this already but keeping a water bottle or washer in your car is a life saver! a quick squirt and rub down with a towel then pop them in the car (that'll stay clean for longer now), once you're home you can release them straight into the house whilst you do more important things like make a cuppa!
When you are out with the dogs it can be a great time to listen to a few classics, but using wired earphones never fails to end up getting you tangled with leads and ball throwing. It is worth buying a pair of Bluetooth headphones so you are tangle free and can take them out quickly and easily.
With there being a fine in the UK for not carrying a dog bag whilst out with your dog it's worth using this tip. Free a card slot in your wallet and put a couple of folded bags in instead, not only are you safe from a fine but you have a backup if you run out or forget to bring some.
One thing that I have found indispensable is having a backpack with the basics I may need for a dog walk kept in my van. It only has a drink, towel, dog treats and bags but the amount of times I've gotten to a walk and realised I have forgotten my main backpack and had drive back is TOO MANY! But no more.