Books, and documentation & examples on floppy discs and CD-ROMs. In the early-to-mid 90s, many programming books came with a floppy disc with example code so you could at least play around with working examples.
Fixing bugs and figuring out how to get code working was quite painstaking work, especially if you didn't know any other programmers. You could simulate this today if you like -- take a fresh laptop that's never seen the internet, go off to somewhere remote with no possibility of internet (yet somehow have power to charge your battery), and try to build a website with only a "Javascript for Dummies!" book, and that'd be a fair approximation.