Place the butter in a pan or pot of a size appropriate to the amount of butter you're browning.
Melt it over medium heat and keep cooking it, mixing constantly with a spatula. It will begin to sizzle.
Once the sizzling stops it means you're close, pay attention to the colour of the milk solids that tend to be at the bottom.
Once golden, remove the butter from the pan or pot immediately.
Use it melted, at room temperature or cold depending on what the recipe needs.