1. You got your sake? Good.
2. You got your tomato juice? Good. Make sure that it is tomato juice, and that it is NOT tomato paste. (NOTE: The only way to find this out is the hard way. Not all tomato "juice" is really juice like you want to drink.)
3. Fill your glass about 40% full of the sake.
4. Pour tomato juice onto the sake, until the glass is almost full.
5. Top off with ice.