Cover the soil up.
Know when to cut down or prune and do it nicely
Grow easy plants
The first incorporates planting things so that they join up, mulching, not amending the soil, and not digging. The second usually includes localised weeding and attention. The third speaks for itself but is about eliminating fuss and being appropriate. I don't like spraying and generally only use light quiet tools. A good hand fork, small secateurs and a little folding saw can achieve a remarkable amount. Mowing I leave to others who like it.
Of course there are dozens of supplementary processes and activities. My rules are just simple guides. You CAN have free will in the garden. You MUST follow your own vision and desires. But plants are not random entities and time is short, so a little understanding is in order.
I have another subconscious, take it for granted rule. Always leave any garden looking noticeably better in the present, but always get something done which is aimed squarely at the future.
A lot of gardening is basically housework outside. We all know that, as we sweep up, gather up, pick up and finally glance up with a wild surmise, asking "What is this for? " "Has someone run off with my life?" That's when you need the vision and the desire.
For most of us, there is a time when no effort is too great. We go through periods where gardening trumps almost every other activity. However most of us arrive at a point of balance where not every simplification or relaxation is to be rejected. I think I started pretty close to there, seduced by ground-cover, adoring the shrub, always reluctant to dig in great loads of manure, although I believed in it, just too bone idle.
Ken Thompson's books have told me only what I want to hear. He's good on feeding and composts, leaving me with the conviction that even using garden compost on clay soils is unneccessay enrichment - leading to mad fast growth - leading to more control needed, leading to more trips to the compost heap. Stick it on the veg is his answer. Time moves gently for the first two years after planting, then it often speeds up and gallops off with your vision.
Mulching with small leafy prunings and lawn-mowings is a good way of reducing effort. As you reap so you sow, dropping them as close to their place of origin as possible, pushing them out of sight, covering the soil. In a large garden this will always work amongst shrubs. At the back of a wide border, dead wood and proto-compost can accumulate, to the good of your garden and wildlife. I have found composted bark and wood chippings completely satisfactory - despite dire predictions by some pundits. The bark in particular appears to be disliked by slugs, adding to its charms. Of course I do feed roses and I'm quite keen on that myccorrhiza, but without any personal proof. Just belief I suppose. Here's a garden planted 2 years ago (not the trees of course), directly into heavy, rubbley soil and mulched with wood-chip.
I am now economically and effortlessly summing up my whole garden at the beginning of the month of September with this photograph of acidenthera murieliae.
For apparently effortless economy, try Man In The Long Black Coat (Oh Mercy version) by Mr D. Here is an entire Gothic mystery where two pieces of clothing populate a drama. That "soft cotton dress on the line hanging dry"! What more is there to say - she was as lovely as an acidenthera. With the crickets in the background you know where we are and the dress is dry so you know that time has passed. Perhaps her name was Marie Celeste. As I listen, I have a sense of utterly conscious control of the material, nothing lost or forgotten. It's a Deep South Wuthering Heights, summed up in two words - "She gone".
Another salient point arises in the song "There are no mistakes in life, some people say". Well now, you could follow that with the word "Discuss". A person who used to line-dry soft cotton dresses may well have gone to hell which could easily count as some sort of major error. We gardeners generally make smaller, more retrievable misjudgements, which nature will kindly cover over with sycamore and brambles when neglect sets in. But without doubt it's best to try and capture the knowledge as they say these days. Mistakes are also revelations.
Here's one - a biggish plant, tree or shrub, growing well, even quickly and healthily, suddenly loses the will to live, dries up and dies. Dig it out, have a look at the roots. How many times have I seen this, they're all twisted round each other and self-strangulation is under way.
Best to give our plant beauties a fighting chance against the man in the long black coat. If you try leaving the bulbs of acidenthera in the garden over winter "They gone" will be their epitaph. True enough the lost laundress of Man in the Long Black Coat may have chosen to go out and search for her risky escape. Perhaps her roots weren't happy, something was being strangled. Perhaps it was something to do with that person in the background beating the dead horse. He clearly didn't put enough effort in, in the right way, where it was needed.