My Auntie Viv, who is an extraordinary person and just finished an M.A in Fine Arts, had a problem with her knee. So went to her doctor and he said that it was wear and tear. She told him that this was ridiculous because she'd had two knees for the same amount of time so there was no reason for one to wear out but not the other.

So I thought about this and started to observe my knee use. Did I use them equally? Did I heck as like. No, I have a leading leg, and it's my left. When I walk up stairs I go left first, so when I walk up kerbs, my left leg does the work. If all staircases had equal numbers of steps we'd use both knees equally, but I think it's kerbs that do it, kerbs and steps up to people's houses, which often have one or three steps. Don't know why, but check for yourself. So if we continue to step up with our leading legs without thinking about it, it stands to reason that one will wear out first.

Today, for Tuesday. I'm aiming to do things with the other side from usual. For example, pressing the space bar on my computer keyboard with my left thumb instead of my right. Try it; it's hellishly difficult. But I've had right thumb injuries - ldeading all the way to my shoulder - and I think this is what's caused it. I've aldready had to switch mouse sides. As I played the piano for years I'm closer to ambidextrous than most, but this is tricky. Even putting my socks on the other side first took some serious concentration.

Tonight I shall be teaching yoga at the hall down the road. We spend a lot of time in yoga balancing both sides of our bodies because it helps to balance our minds. If you do a yoga posture on one side then come back to the centre it feels seriously odd, as if one side of the body is awake and the other is still snoozing. After all that we do tend to come out feeling mentally balanced at the end of a class.

So for reasons of practical joint wear and tear, and to aim for a calm, balanced approach to life, have a crack at left-right equality. Carry your bag with the other hand. Some things we can't change, like where the brakes are on a car or the Oyster pads in a tube station, but otherwise, put the balance back and see how you feel at the end of this Tuesday.

Here's a theory about the creative process. It involves three different abilities. One person might have two or all three of them, or you might need several people for just one of the essential triad, but it goes like this:

1. Someone to have the idea.

2. Someone to turn the idea into a practical blueprint.

3. Someone who can follow the instructions and make it real.

If you just have ideas nothing happens. That's one of the reasons that you can't patent an idea. You get lots of people complaining that they thought of something first and now someone else is making money out of it. Tough. If you don't get parts two and three organised, your grand idea stays imaginary and someone else takes the credit.

If you can translate ideas into a plan, then you're on your way.

Then you've got to find someone with the practical skills to turn it into something that others can experience.

Artists do all three. Think of singer-songwriters or painters. Part one can be a creative team, or an individual, part two can be your reliable backroom support team: architects, pattern drawers; sketch artists. Part three could be a symphony orchestra or a building contractor or a team of embroiderers.

I realise that it's not the world's most earth-shattering creative endeavour, but I've been working on socks. I knew what they wanted to look like, knitted four pairs before I got them perfect and have now written down the pattern so that everyone else can knit them too, if they've got the part three knitting skills.

How does it work with you? Are you best at one part of the process? Are you looking for someone who can do the other bits? It's something to think about when you're making your ideas real.

Some of us have too many ideas, and some of us don't have quite enough. I err on the side of far too many to fit into one lifetime, so I've decided to share them. I really can't stand waste. I hate to see an apple tree at the bottom of someone's garden, then day by day watch them all fall off and rot. I love it when - like yesterday - I pass a house where they've picked their spare apples and put them at their garden gate, inviting anyone who needs them to pick them up. They even put out spare plastic bags so people could carry them home easily. What stars! I'm off to put a thankyou note through their door.

If you've got some spare ideas, see this as a garden gate where you can put them out for anyone passing to pick up and use.

And if you're having an emtpy brain day, come here and reap the harvest.

Today, as it's apple time, if you've got some spares in you garden, go get them and put them by your front gate. If you don't have a gate, use your imagination.