Add a prefix to your labels

To keep track of (the target of) your labels you might want to add a prefix to their names indicating the thing they are referring to. E.g. sec for sections, eq for equations, fig for figures etc. It is common to separate the prefix with a colon from the label name like in the following example:

Then when you read your code you always know that \ref{sec:test} refers to a section.

In some cases the colon can cause troubles, e.g. when you type a french document with babel, varioref, hyperref and cleveref (see this and this post on TeX.SX for example). In that case you may use another character to separate the prefix.