Trouser length
Shortening or lengthening a trouser is one of the easiest and most basic adjustments to make. In fact, dress pants are often sold unhemmed, with the assumption that the purchaser will take the trousers to a tailor.
The trouser should always end above or at the top of the heel of the shoe, but it is worth mentioning that a narrower leg will always sit higher. A slimmer fit trouser may not physically be able to fall past the top of the shoe, so keep this in mind when purchasing.
The "break" is the small wrinkle caused when the top of your shoe stops your trouser from falling to its full length. The break should be a minimal feature, only one or two dimples or creases.