I started biking again in the past couple weeks, after a pretty bad Northeastern winter. It rained here in Jersey yesterday, while my bike was locked up outside. What should I put on the chain to prevent rust? I was thinking applying some WD-40 before I go out could help, and I have a ton of that lying around. Are there better things to put on a chain/bike to keep it nice (eg, lube) and what would those be, and how much should it cost? Thanks in advance.
Edit: It's a steel frame