First of all, make sure that the employee has signed them. If this is not the case, then they could be confiscated.
Next, decide where you would like to go and take them to a city ticket office if possible to "ticket' them. If not, you can also do this at the airport. Make sure that you are listed on the flights about a week out before departure. There is a number that you can call to list for the flight. Also, the employee can do it very easily online.
Check the loads either by calling the VRU line or by calling the employee. They should be able to give you an idea of what to expect. If you are trying to go to Hawaii or Europe in the summer, make sure that you have enough money to buy a ticket back home if necessary. Hundreds of people can get bumped in a day during busy times. Be very flexible. Travel on off peak hours and in the middle of the week will likely advance your cause.
Most important of all, remind the people that are travelling with you that these are for standby only and will not gaurantee a seat. If you are assigned a seat, always take what they give you. Check with the employee for the dress codes for first and coach class. This will prove to be extremely important later. Never ever argue with the ticket agent or the gate agent, even if there is an obvious problem. If you feel like they have done something wrong, make a mental note of the person(s), the location, and give the details to the employee. There have been a lot of problems lately with people raising a scene with buddy passes over seating, the dress code, or other issues. All too often, the employee has been reprimanded or even worse, had their benefits suspended. I trust you will do OK though. Getting an idea of the loads and alternate schedules for backup plans will help you a lot. Enjoy the trip!