Cobbsie, you can get face masks like nurses wear in isolation rooms. The simple cloth-like mask will help keep most of the the fumes out of your nose and lungs. You wouldn't need to wear it except while standing over the lye solution, so you could use it over and over again. They are available in many many places, including drug stores and some hardware stores.
I also mix my lye solution in the sink. I turn on the fan over my stove (not really near the sink, but in the same room) and don't lean over the solution while stirring. The only times the fumes have bothered me were when I mixed it with things other than water that lead to faster heating. Most of the time, I don't have a problem with the fumes.
When I was young, my mom taught me to clean my oven in lye solution, which I prepared myself in the utility sink. Then I'd take the stove parts and soak them in the lye solution until all the caked on stuff fell right off. So I came to soaping without any fear of lye. Back then, the only precautions I took were thick rubber gloves and old clothes. But the solution was much weaker than what I use for soaping. Still, it was caustic as evidenced by how well it cleaned the oven and stove parts.