The letter 'u' ordinarily makes two sounds in English: a short sound as in 'hug' or a long sound as in 'huge'. However, this long sound sounds more like [you] than [oo]. There are some spelling rules you can remember to know when to use a short or a long sound, but sometimes it is not as clear.
I made a video with some common examples of this long 'u' sound: http://goo.gl/MYSU1D
Do you know a word with a 'u' you are not sure how to pronounce? Are there any letter sounds or combinations that are tricky for you?