dont smoke anymore, but back in the day I used to use a plastic activated carbon fish tank/aquifer filter with scented dryer sheets stuffed in the empty spaces.

take a hit, hold it for as long as you can to absorb a lot of the smoke, then blow through the filter.

I've always had the idea of a small room or tent, with a carbon filter exhausting outside. While your clothes may smell, the majority of the smoke is filtered and thrown outside.

HEPA filter

I smoke in the bathroom with the vent fan running. Ain't perfect but it's keeping the stink out of the other rooms

Don't think it's possible. Smoke smells, so do it outside if you can. Other than that you can vape (which also has its own smell) or take edibles (assuming you also like that experience).

I only smoke occasionally and usually as a group activity, but always outdoors. Edibles are kind of a hassle-free, healthier, less invasive, and more cost effective option. That said, there is something about the shared experience of passing a joint around.