Showing him slapping a mosquito at the begining indicates murder.
Lots of jump cuts.
The title of Dexter, writing is blood red the background is very pale like it has been carved on a dead body, this is show after he has opened his eyes to show hes awoken and ready for the sequence of his day.
Jump cut from one blood spot to another two, creates more drama and tension.
Lots of jump cuts adds mystery and addiction making you asking questions.
Shows him locking the door maybe to show hes's locking away secrets, it shows him pulling the key out relating to him pulling aknife out of somebody.
The sequence jumps from one thing hes doing to another mainly emphasing things that relate to murder or are simlar that make you think of murder.
Also using the jump cuts it makes the routine seem more odd and unatural which relates to the fact that he himself is a bit weird and unnatural.