I am a gasfitter licenced for two years after completing a six month course. I am british but live in Canada with Canadian citizenship. I have a sister that lives in perth. What are my chances of getting a visa/ the process involved?

Appreciate any help

Thanks

Start here - www.immi.gov.au

Gas Fitters are in demand and are also listed on the new immigration list.
Your sister would be able to be a sponsor, this reduces the number of point required.

I am no expert though and would highly advise you to contact a registered migration agent. One that come to mind is http://gomatilda.com