If your thinking of doing agility start small
https://www.youtube.com/watch?v=BUIDh1CT4bI&feature=PlayList&p=775E7225295CD511&index=20&playnext=2&playnext_from=PL
then build up
https://www.youtube.com/watch?v=BUIDh1CT4bI&feature=PlayList&p=775E7225295CD511&index=20&playnext=2&playnext_from=PL
then build up