How to say it - /ʊə/ & /ɔɪ/
To make the /ɔɪ/ sound, say a long /ɔː/ first, then move your tongue up and forward. Widen your lips for the /ɪ/.
An interesting word that uses this sound twice is 'toy-boy' /tɔɪ bɔɪ/. A 'toy-boy' is a handsome young man who is the boyfriend of an older, richer woman.
Video of Mouth
Follow the instructions as they appear in the video.