Agreed depends on the job and type of employer you will be approaching, as to how to dress.

If you are registering with employment agencies, always take their advice on appropriate dress for the role you will be interviewed for - they will know the client company and can advise.

When first going to employment agencies, would advise to dress in smart clothing - female - skirt/ trousers in dark colour, with blouse or smart plain long sleeve top and a tailored jacket. Male - not necessarily a suit, but smart trousers, shirt with or without tie and jacket. Sounds formal but first impressions do count always, even if the job you go for everyone wears jeans. Employment agencies prefer a client who looks serious about getting work. Remember you getting work will pay their wages too!

Good luck.