I would suggest basing your teaching around functions and situations.  Think about what they will have to do in the UK and what different situations they are likely to face.  For example, they might need to disagree politely with a teacher or participate actively in a debate.  Common situations might be meeting a friend at a party or planning an evening's entertainment.  I guess academic speaking skills are a bit more straightforward to teach, normally centred on progress towards a presentation.  In all situations, I suggest you provide plenty of models and examples.  I think the internet is really useful for that.  Most important in teaching speaking is motivation.  Think carefully about what will interest your students and don't be too downcast if you get that wrong a few times.  Good Luck

Teaching in China has become increasingly competitive.   If you don't have previous teaching experience you may still qualify but training is required.