Seasonal jobs that might turn permanent - what worked for you?

I am looking at seasonal jobs around Baltimore that might lead to something longer. I would rather hear the honest version than the polite one. Hours ramp up in the coming weeks. Is it worth applying to several at once?

Keep a list of supervisors' names. A reference from one of them helped me land my next job.

I was converted after one season because I showed up every day and volunteered for extra shifts. Managers remember that.