It's tricky to get accurate color balance when mixing tungsten and daylight, if not impossible. As far as ratio goes, again it depends. What is the scenario you are trying to shoot? A little bit of tungsten (desk lamp) will warm up a picture, but as a main light will make everything orange/yellow (DL film).
Regarding film, I think there's a much better selection of daylight (Astia especially) film than tungsten-balanced. So I would use daylight and a CC filter for tungsten shots. (Tungsten film looks weird even if CC'ed to daylight.)
Just my opinions, hope it points you in the right direction!