You can format text for output in C using the printf() function with placeholders, also known as format specifiers, denoted by a percentage symbol (%) followed by a format code (such as %d, %f, %c, or %s). The format specifiers are used within the format string to specify the type and layout of the output. The corresponding arguments are passed to the printf() function, which automatically replaces the format specifiers with the given values, ensuring the desired formatting is applied to the output.