If you're thinking of creating magic, try thinking of what you'd like to achieve FIRST. Once you've done that, you've got hundreds of years of method ready to back you up.
Are you trying to achieve something beautiful? Puzzling? Scary? Think of it like you were writing a story. What will happen to the characters?
All too often, especially in the crowded world of card magic for example, you will see contrived tricks that involve cards that face this way and that, piles, numbers, signatures, etc. If you go back and think about how these effects came to be, usually the answer is that a clever method or handling was discovered. Rarely is it the case that someone wanted to "find a chosen card", say. Why? Because it's been done! It's been done a million times over! No one wakes up and wants to find a card, but that's what ends up getting "created" because they are thinking method -> effect instead of the other way around.
No one (and I mean no one) cares how you came to find the chosen card. All they remember the next day is "he found my card."
On the other hand, even if you're stuck and dying to do a card trick, think about what is happening. What is the end result, what is the EFFECT. Then, think about the journey. How will I get there? Will this be a fun experience? Lastly, think about the method. Look at what needs to happen and your constraints, then figure out the shortest path to solving it.
I think you'll be blown away by what you come up with.
