crash!!

how do you change to dx11 with steam? the forum How to force DirectX11: 40% Less memory use doesnt say how to do this with steam

how do you put this code in using steam?

ty but i have reinstalled this game many times with no results. i have also found that it only crashes if over 70% memory is being used.

when i get into the game i launch a rocket, it works. then when i exit the rocket/ plane to build another one i enter the spaceplane hangar and it crashes. this is the file error: Unity Player [version: Unity 5.2.4f1_98095704e6fe] KSP.exe caused an Access Violation (0xc0000005) in module KSP.exe at 001b:00e7a6ef. Error occurred at 2016-10-01_014424. C:\Program Files\Steam\steamapps\common\Kerbal Space Program\KSP.exe, run by Belinda. 77% memory in use. 3225 MB physical memory [719 MB free]. 0 MB paging file [674 MB free]. 2048 MB user address space [95 MB free]. Write to location 00000000 caused an access violation. Context: EDI: 0x00000000 ESI: 0x2a12b2d0 EAX: 0xcdcdcdcd EBX: 0x01555558 ECX: 0x00555556 EDX: 0x00000000 EIP: 0x00e7a6ef EBP: 0x14c3f944 SegCs: 0x0000001b EFlags: 0x00010206 ESP: 0x14c3f924 SegSs: 0x00000023 Bytes at CS:EIP: f3 ab 85 d2 74 0a 88 07 83 c7 01 83 ea 01 75 f6 my system running is: GPU= GEforce GTX 750 CPU= intel core i5-4460 CPU @ 320 ghz operating system: windows 10 home edition