How to run multiple mods at once?

[Polygemus]

Hi, I did a search but nothing shows up. I downloaded the LowResTextures Mod and the LowResLeaderhead Mod. How to run the two mods at once? When I go to "Advanced" and "Load a Mod" I am only able to run one at a time.

If possible pls be clear and specific in the reply as I am not that IT savvy. Thanks a lot.