Go to here:
reshade.me/#download
Extract to a folder somewhere.
Run 'Reshade Setup' -> Select Game -> Browse to the bf4.exe file (bf4.exe for 64 bit, bf4_x86.exe for 32 bit)
If you have reshade only, then skip this bottom part, if you also have sweetfx then read on
Go here:
sfx.thelazy.net/games/game/280/
Download a preset you like, put it in the SweetFX folder created where the bf4.exe file was.
Delete the SweetFX_settings.txt file and replace it with the new file. Rename the new file to SweetFX_settings.txt and ...
Voila! Now just normally open bf4 from origin or shortcut and use scroll lock to toggle reshade on and off.
