Multi-Tasking

I was all excited because I got a computer program that will allow me to access my entire home computer from work.

My plan was to do some "posting" (totally irrelevant and boring work thing) while I watched the conference tournaments.

The posting went great, but I just posted for 3 hours and then realized I really had no idea what happened during the games.

Can someone who is good at multi-tasking please explain to me how to pay attention to both things at the same time?