In case you did not read this in another thread.
here is some information I found on the web. It is not about Aikido but about learning to play the oboe. However the advice works for anything.
THOUGHTS ON PRACTICING
©1999 Martin Schuring
"The most important thing to learn is how to practice. If you learn that, you will certainly learn how to play. Many students (and professionals too, for that matter) don't like to practice, don't do it enough, and don't use their practice time productively. Many students don't even know what to do when they are supposed to be practicing. A lot of doodling and messing around masquerades as practicing.We all know players who assert that they practice three or four hours a day, yet are rarely prepared for lessons, much less concerts. This page is intended to help with these problems.
How to Practice
How you practice is the essential point of the entire subject. If you don't do it well, it doesn't matter how much you practice, what you practice, or how often you practice. Practicing is essential to progress, but done inefficiently, it can actually be a barrier to progress. For many people, practicing is a process where they take something new, play it badly, and try to improve it through repetition. The reason they play it badly is simple: they can't play it yet. So, they begin again, play it badly some more, maybe twenty times more, and quit for the day having learned little except perhaps how not to play the passage. There is no other process in life that people begin in this way. If I ask you to build me a bookshelf, you wouldn't just collect a pile of scrap lumber, nail it together quickly, and then look at it - crooked isn't it? Instead, you would likely make a drawing, decide dimensions, buy the correct amount of wood, cut it carefully, etc. Done in this way, the assembly of the bookshelf becomes the easiest part of the process, just as the performance should be the reward for careful preparation.
Accomplishing this goal is not as difficult as you might imagine. The answer is contained in four simple words: NEVER DO IT WRONG. Never do it wrong. Every time you play the oboe, do it right. Of course, you should use good posture and play with a healthy sound production on a comfortable reed. But, you must also play the right notes in the right place with the correct fingerings. Every time. The secrect lies in repetition - frequent CORRECT repetition. Both words are important - frequent AND correct. Never do it wrong, and do it right often. If you play something ten times right and ten times wrong, even slightly wrong, you've just wasted however much time it took to accomplish that. Even worse, those ten wrong repetitions are stored in your brain for future retrieval - usually during a concert. Ninety times right and ten times wrong is much better, but remember that those ten wrong ones are still in there waiting. Play it right every single time. You have only one chance to play it right in the performance. That means you must be able to play it right every time.
Playing it right every time isn't nearly as challenging as you might imagine. All you have to do is slow it down.Play at a speed where your brain can operate faster than your fingers. Anytime you can no longer control what's coming out of the oboe, you will make mistakes. Use your metronome and slow down. Only speed up when you start to feel confident that nothing could cause you to make a mistake.
The brain commands many complex physical actions in a way that we regard as automatic. Throwing a ball, tying shoelaces, eating a meal - all are complex actions requiring thousands of muscular responses. But we can do them almost without thinking because we have repeated them so often. Musical vocabulary must be learned in the same way. Learn it once, learn it well. The difficulty is in finding the patience to repeat the passage (correctly) often enough. It may take a thousand times or more for something difficult to become secure. Worse, with this method of working you will very quickly realize just how much work remains - when you're looking at sixteenth notes and playing them as quarter notes, it's hard not to become discouraged. You may lose patience and resume the old sloppy way of working. Don't. With the accurate method of practicing, you will eventually learn the passage. The other way has only ignorance as its advantage - you will never learn the music well, but you may not know that until the concert.
How Much to Practice
How much to practice depends a great deal on the age of the student and his/her goals for the instrument. For a twelve year old beginner, thirty or forty minutes a day may well be ample. For a college music major, forty minutes should be the minimum amount of time spent warming up for a practice regimen of between three and five hours daily. Time spent beyond five hours seems to me to be unproductive - the body and mind are too tired. Less than three hours, and improvement crawls to a snail's pace.
Split the practice time into several sessions during the day. Take a break of at least ten minutes each hour and go do something else. Talk to friends, read a magazine, but don't rush off to make a reed. Take a break. Your body and mind will thank you.
Two other things are as important as practicing enough - practicing carefully (see above) and practicing every day. In many ways, practicing is just like going on a diet. You cannot go on a diet three days a week. You cannot go on a diet for just a week or two. After a week or two, you have merely experienced all of the pain and irritability without seeing any of the reward. But after a year, besides having a whole new appearance, you also have a whole new world of good habits that will keep you healthy for the rest of your life.
Students who don't practice enough usually regard practicing as work and drudgery. More practice means more work and more drudgery. This reaction simply means that the student has never practiced enough to experience the reward. Trust your teacher; do what he or she says; do it well. After six months, improvement is guaranteed. By then, you'll be enjoying it so much you'll never go back to muddling through.
After not practicing well for many years, or not practicing enough, many students report that increased practice only makes them sound worse. Since that can't possibly be true, consider that you are merely more clearly aware of your shortcomings. After a few weeks, when you've worked them out, you can start to improve.
There is no such thing as being too well prepared. You get one chance to play something correctly. At that point, you don't want a 50% chance of accuracy; you don't even want a 99% chance. You want it to be right and give the listener the impression that it was easy. Remember - in order for it to sound easy, it must be easy. There is no faking this."
As I said this was from the website http://www.public.asu.edu/~schuring/Oboe/practice.html