Hecka simple friend. I was using NTR before, but this really is more convenient.
In your luma folder, create a folder called "titles". In that, create a folder for the MHXX stuff named "0004000000197100" (the title ID of MHXX). Inside that, make a folder called "romfs", and then just put all the patch files (the arc and table folders) inside that.
After that, you just enable game patching via the Luma Config Menu and it just works. Great stuff.
Just to illustrate the folder format:
luma
| titles
--| 0004000000197100
-----| romfs
--------| [Patch Files]