Fill the container with vodka - be sure the beans are completely covered in vodka.
Place the bottle in a cool closet or pantry and allow it to sit for 4 - 8 weeks. I have found it good after 6 weeks.
To reuse, once a bottle is ½ empty, refill with vodka and allow to sit for another 8 weeks.
Notes
I prefer to use vodka to make my vanilla extract and use the cheaper brand. After testing, no difference was found in the taste of cheaper vodka vs the more expensive brands.