the vac does make it much easier!!! and an enlarge master cylinder fluid bottle would make it even EASIER!!!
but to explain how it works real quick...
1. you hook up the vac handle to a container, then to your bleeder nut on your caliper.
2. take off the master cylinder reservoir cover and fill with fluid.
3. pump up the handle on the bleeder and crack open the bleeder.
4. watch for bubbles and the amount of vacuum on the gauge.
5. close bleeder nut and pump up brake handle (not always necessary, but i like to do this to help ensure a good flush)
6. top off master cylinder reservoir if necessary.
repeat steps 3-6 until you have nice clear bubble-less fluid coming out of the bleeder nut. be sure not to allow any air into the system while the bleeder is open. otherwise you have to start over
i hope this helps!!!
oh ya, if you have 2 calipers, then repeat this step for each caliper