There are points you have to accumulate before you'll get a working Visa.
Start here:
www.gov.uk/browse/visas-immigration/work-visasIf you have a parent/grandparent with a UK or EU visa will be a lot easier. In short you may need to be sponsored by your employer and they'll have to prove they can't find anybody local to fill the position. Age counts too, even how much you earn can count. I remember having just enough/not enough points a few years back as the exchange rates fluctuated day-to-day.
I've found the only way for myself is to get sponsored, I work in one of those "specialist" fields.
I hate to break it to you but I don't fancy your chances as a teacher. I may be completely wrong of course, judging by
how much a grad teacher makes in WA!!!Edit: Shortage Occupation List
www.ukba.homeoffice.gov.uk/sitecontent/documents/workingintheuk/shortageoccupationlist"Secondary education teaching professionals (2314)
ONLY the following job title within this occupation: Secondary Education Teachers within the subjects of maths or science"
