I would suggest trying to get some experience in this country first so that you can get a reference. If you live near a university or college, they often run language classes during the summer for foreign students. Perhaps you could enquire about sitting in on a few classes first of all to get a feel and then ask if you could do a small slot in one of the classes. There's a language school near me, Stirling, and they have agreed to let me do this, I think it'll be really beneficial.

Another idea could be to try and do some private one to one tuition to get experience, you could advertise your services locally. I have often seen ads in shop windows requesting English lessons from people who have moved here and speak little English.

Good luck and let me know how you get on!