Mindfulness, conciousness and directing attention

Often as part of mindfulness meditation (at least the Westernized form with which I am familiar) we can practice awareness of breath, parts of the breath, arising thoughts etc. However, if the aim of mindfulness is to be in pure consciousness, how can we at the same time be directing attention to something? Wouldn't this constitute a 'doing' which arises from thought rather than from consciousness? EDIT: I have accepted an answer that seems to be the most useful for me right now, but I can see that this a complex subject and I will certainly not ignore the content of the other answers.