I think what Gui42 meant by 90% practice, 10% performance is that 90% of the time you practice, 10% of the time, you perform.
Although, the bit about performance during a performance, being the main thing that makes the magic, well that's great advice. So work on that.
As far as performing for people Gui42, there are several places to perform. The most common place for people that are still in school, is to perform in school. You can also perform in malls (with permission of course), or in stores (once again with the managers permission).
What's the best way to draw crowds and perform in school?
The best way to perform in school is to get in an area where there are lots of your fellow classmates. Take a friend with you and perform a trick for him. If it's well performed and he freaks out, it will draw attention to your performance. People will start coming over to look and see what's going on.
What's the best way to draw crowds in a mall?
It's best not to approach people in a mall, most are there to shop, not see magic. Some are just strolling around aimlessly, but it's hard to find them. So, there are two ways to draw a crowd, because even though they're shopping, if a bunch of people are gathered and watching something, then they want to see. You do actually do the friend method you would do in the school setting. Take a friend with you and perform some magic with him, if he is amazed, people will start crowding around and watching. But, another way you can perform is to draw in the aimless people strolling about the mall. Just simply sit somewhere and do some simple things with cards. Do some flourishes, do some easy color changes, just do something. If an aimless person walks by they will probably get interested and stop and ask if you do magic. Then the performance starts and if you amaze them, a crowd can gather.
There's so much more great advice out there and in my mind, but, since I don't have all day to type and have to leave in five minutes, I'm gonna have to end there. Hopefully I helped in some way! Peace!
Tyler