This was once explained to me in great detail, by someone who obviously had no idea what they were talking about and had simply printed it off the internet.
Basically, when something is dropped (in this case, a piece of toast or something similar) it can only spin X amount of times before it hits the ground, for toast it is normally 1.5 times. There are 3 ways we can change this, and make our toast land the right way up:
1. alter the rate at which the toast falls.
e.g. throw the toast at the ground, it will spend less time spinning and therefore complete fewer rotations before hitting the ground.
2. Alter the rate at which the toast spins .
e.g. while the toast is falling, catch it, spin it and let it continue falling.
3. Alter the height at which the toast falls from.
e.g. get a higher table. of course this causes a problem as most tables are positioned at the most convenient height for humans to use, so if you get a higher table, you will need a taller human. However, humans do not grow more than two meters or so tall, because falling from much more than that height can be harmful to ones health. So as well as the person needing to be taller to deal with the higher table, they will also need a revised bone structure to deal with any issues that may arise from being that tall - some kind of supersized mutant.
Of course you could just be more careful with your toast...
