You don't really need a lawyer. I did it myself but it's always good to hire someone to look through your paperwork I guess.
The process isn't complicated. Your employer needs to fill out a form and provide you some documents and it might be sensitive in some ways.
If you apply under semi-skilled, you would have to wait for 9 months and you will have to do an English test(not like it's hard anyways). However, if you apply under international graduate, you can do it right away as soon as you get hired, there is no waiting period. BUT, make sure your diploma from a recognized college.