I have been really happy that I made the investment in an electric can opener.  I have been using a manual can opener for ages and finally decided to make the upgrade.  This has been a game changer.  All you need to do is hold the can close to the circular front opener, then press down on the top handle to lock it in place, then press firmly and the can will automatically rotate and open.  The can latches into place so you know it has a firm grip.  You can then let off of the top handle when the can is opened, then enjoy.  Mine also came with scissors in the back of the unit for easy use and storage.  Highly recommend this to anyone considering!