Well look at intention this way. We form habits using intention. Once they are well established habits, the intention used is most of the time pretty normal. In order to form new habits however, one usually needs more power of intention. Intention is one of the basic building blocks of lucid dreaming. Daytime exercises will serve to strengthen that intention/memory, but effort will always be necessary. Not only can you attach intention to actions like you mentioned. You can use all aspects of experience to trigger intention. Any dream sign really would work as an intention/memory trigger.

Personally, I find it essential to produce specific feelings before I go to bed that will trigger awareness in the dream state. Everyone is different though.