On C64 you could just type rundot save I think, stick a tape in and press record. I had a little inlay with the counter numbers for each cheat on the tape written on it.

I remember on the C64 they used to have ‘pokes’ which were written in assembler.

You’d have to manually typing 500 lines of it. Of course, it almost never worked. The times it did work I used to save it to a tape, I think I had about 9 cheats on it :)