One of the main problems that English speakers have with French pronunciation is producing the difference between the ‘ou’ (u) and ‘u’ (y) sounds in French. This is mainly because neither of these sounds exist in English.  We do, however, have a sound ‘oo’, for example, as in ‘loo’, ‘too’.  Because of this, many English people pronounce the ‘ou’, and the ‘u’ in French in exactly the same way as this ‘oo’ sound in English.  This makes it rather difficult for French people to understand us.
I didn’t even realise there were two different sounds until I visited France on an exchange trip as a teenager and the Maman of the family explained to me that I wasn’t making the ‘ou’ sound very well.  She told me I needed to be making a noise like a dog barking, and proceeded to imitate a French dog for me (which, unsurprisingly, barks with a French accent!).

Bark like a dog!

Sadly, I can’t bark like a French dog for you on this blog.  But to help you out with your pronunciation of these sounds, here is an article by someone who has described the difference between these two sounds in a very helpful way.   Have a little look at it and see what you think.  I think it’s a really helpful summary.

Lucky children
Lucky children

You can also check out my YouTube tutorial for Old MacDonald had a Farm, where I explain how to produce the u (y) sound (jump to the 52nd second to find it!).  I chose this particular sound for this song to give the children and adults in my classes opportunity to practise it.  The great thing for small children is that we don’t have to tell them how to make these sounds.  If they are exposed frequently enough, they will reproduce them very naturally.  They are very lucky, aren’t they?
Have a practice at producing these sounds and tell me how you get on.  I bet with some practice you’ll be sounding very authentic in no time.