I use these:
https://www.amazon.com/gp/product/B00007LVDL/ref=ppx_yo_dt_b_asin_title_o00__o00_s01?ie=UTF8&psc=1

They're great because you can print your cards directly onto the sheet, then pull them apart. Really useful if your game involves multiple copies of the same thing, since you can just copy and paste instead of writing the same damn thing over and over. Also, typing is faster than writing anyway. It's 13 USD for 400 cards, which is cheaper than 100 of the suggested blank cards + sleeves (~20 USD). You can't reuse them, but if you buy 2 packs for $26, you should get a lot of use out of them, and are basically paying a few extra bucks for something that's waaaaay easier than writing out 800 cards by hand.

The sheets are kind of thick though, so I'm not sure if home printers will do the job right. I've only ever printed with the copier at work (shhh, don't tell my boss).