Had a bit of an advantage over the other guys because I could type.
Most of the guys (and yes, they were guys...) wrote programs on pre-printed Fortran forms that they'd hand over to women who punched the cards.
This picture is from the 'sixties, but it was still like that in the 'seventies, most places:

When I was a kid my mom had a friend who had home access to a mainframe. He used a portable teletype (no such thing, really) and an acoustic modem. In those days you weren't allowed to attach anything to the actual phone lines, so you placed the telephone handset directly on the modem and dialed the number on the phone. Yes, dialed.
I'd save programs I wrote on punched paper tape which I'd gently hang in my closet at home, leaving my clothes on the floor.
I've been obsessed with computers my entire life.
One summer I took my two year college technical certificate and got a job at a major mainframe computer manufacturer. But the place was already dying and three quarters abandoned. It was spooky sometimes, you could imagine yourself living in a post-apocalypse world. Where are all the people? Nobody ate lunch in the huge cafeteria even though it was kept clean enough for the county health inspector. Any employees who could had already fled for greener pastures. There was still some contract work repairing and refurbishing stuff like 10 megabyte hard drives as big as washing machines.
My supervisor let me take home tons of computer crap that I'd incorporate into my own home built computers. I'm sure the security guys wondered what the hell kind of place they were working at where strange young guys like me were allowed to take random stuff home. I still have a lot of it (the smaller stuff at least) in my junk boxes.