Carry a list or a notepad with you.
Write the new word and its meaning (and maybe an example too) in a small notepad that you can carry with you and read whenever you have a spare moment (or some people keep them in their smartphone). This can be read while you are sitting on a bus, on the underground/subway, or while you are in a waiting room. This will help you see the words more than once and will help them stick in your mind.
Brought to you by Nomen Global Language Center, in Provo, Utah.