KAYJAS

When I come over I will assume I will not get a job in my field (design eng.) right away so I will take anything just to get some money rolling in. How easy is it to get non skilled/casual work that would pay enough to pay all monthly bills and put food on the table?
What is the aptitude test all about? I might be clever in my job but never been good a quick answers with time constraints!!
I could take the easy route and not leave my cozy job here in the UK!!