My work entails me to become a multi-tasker and be able to fulfill the tasks in a day to day basis. It is very challenging but I have been trained on my previous job to become one.
To become a multi-tasker requires an organized work system and a lot of presence of mind. To know the priority tasks over the lesser ones. If the people are coming to you that needs attention, you have to know who to prioritize.
If you are working with computers and working online, you will be trained a lot to be a multi-tasker since opening a lot of window tabs is already an easy task. Joggling with various websites is already part of the work system. You just have to watch your heartbeat when multi-tasking, you just feel under stress always.