Being a musician one of the first things I have learn't was the proper techiques for
practice and also quickly realised that practicing the right way can take a tenth the time that practicing the wrong way, and also you learn a lot more.

I have just recently started taking up magic seriosuly and have applied a lot of the techniques I use for practicing music to magic. If you think a lot of this is stupid then feel free to say so.

Technique 1 :
Everyone knows that your mind is a LOT faster than your hands possibly are, therefore it makes sense to practice with your mind first. When startintg a new slieght the first thing I do is go
over every step in my mind . Most people can do this after they know how to do something. For example, take the two handed lift, try this without any cards just in your mind, easy?, you can even almost feel the movement of the cards against you skin etc. Taking this one step further you should be able to do this before you have even tried the slieght. Start by doing it VERY slowly in your mind , slower than you would ever do it and just keep running through it . It is important to note here as well if you practice it slow enough then it is IMPOSSIBLE to make a mistake , so you should be able to do the move without ever making a mistake . If you practice this way then since you have never practiced it wrong it follows you will NEVER get it wrong. After you have the move up to a reasonable speed in your mind ( not to fast ) then try it at a slower tempo with your hands, its amazing how fast you can pick up a new move this way .

Technique 2:
Speed, this is the main area EVERYONE goes wrong, in music and magic. Practice brings precision, but speed comes after. This is important a lot of people concentrate on getting things faster and faster , think of speed as totally un-important and just practice making the moves smoother and smoother you will find your speed will also increase. I dont know if anyone else does this but also I have been using a metronome to time the rhythm of certain moves. This is very usefull as it means you can always keep a set rhtyhm going on a move and therefore every time you come back to pratcie it, it should be the same as before. Also even though I suggest speed is not important, you can attain much higher speeds than you would think possible with the use of a metronome. Say you start at 50bpm and the move takes one beat of the metronome. A technique you could use would be say the next hour, day,week , month increase the metronome by one beat only i.e 51bpm , using this technique you can always get to ANY desired speed. 1 bpm is almost no different from 50 but do this say 50 times at you own leisure ( keeping of course a strict routine of when you increase by 1 beap i.e increase by one beat every week and the speed will have doubled by the end of the year ) and you will be twice as fast and yet it will seem as though all you have done is practice at the same speed for the whole time. Nearly all musicians use such a technique to achive impossible speeds.

Technique 3:
Everyone knows this , but it is better to practice for 5 minutes a day than sit down on saturday and do a 3 hour stretch. Also if you do like practicing for 30 minutes a day say , you will improve a lot more by taking a 5 minute break aftre 15 minutes , this allows your brain to process the information. Many people think it is good to practice for 10 minutes before you go to sleep ( in your mind , or physically ) , then during the night your brain processes the data.

Also always remember before practicing to WARM-UP , dont start going as fast as possible , you will find you if you go at full tempo straight away you can only practice for about 5 minutes. It is probably also worth reading some documents on RSI many of which are avaliable on the "net" , they give a lot of information on how to prevent it. There are lots of other things I havent mentioned such as proper breathing , many people grit their teeth or hold there breath when pulling of ceratin moves and this is bad for the techique as well as a bit of a give away.

Another idea I had was when practicing in front of a mirror , put the mirror at a much more severe angle than the audience would ever see and then practice so the manouvre is flawless at that angle. This way if you can do the move at a much harder ability when performing it , it will seem EASY. When practicing a piece i will always practice it so I can play it a fair amount faster than when I perform it , it makes it so much easier to play it at the right speed. And yes I realise a lot of what I say seems to conflict with each other , you'll have to use your own judgement!.