How do i get a discount code for rimworld and where do i put it.

[Maxsio]

I want to get rimworld for cheaper.

[Washell]

You can try finding a coupon, if they exist at all for Rimworld:
https://steamcommunity.com/groups/Coupon-Trading-Group

Or wait for the Winter sale starting late December.

[Crazy Tiger]

The Rimworld devs in general don't want to discount their game too much. So you could wait til the Winter sale and see another 10% discount, but it might be wishful thinking to get more than that.