Honestly, I've been in the UK since last spring and have applied for countless positions, from professional work in my field to temporary part-time retail, and haven't had any luck. The only work I've gotten was a part-time retail job for the holidays, and it ended up being kind of sketchy, waiting until the end of the position to reveal that I'd have to invoice them as self-employed to get paid.
My Canadian spouse hasn't fared much better, with just one two-month temporary position. We've both had to register as self-employed in our fields and find work across the pond. He has some British freelance clients, while I don't - mine are all in the US.
We're considering moving to a different part of the UK to see if we have better luck finding jobs but are wary of running into the same issues in a different place.