Small employers hiring around Boston - what worked for you?

I asked around at a community meeting and got three leads. I am in Boston, in case local advice matters. They prefer people who can start within a couple of weeks. What do you write in a cold email?

A short email with two sentences about what you can do and your résumé attached worked for me. I followed up after a week.

Small employers often hire on recommendation. Ask neighbours, former co-workers and your library.